Campus Killer: Physics Genius Who Bragged to His Girlfriend About a Murder

[00:00:06]A physics master is the last person to see international student Yingying Zhang before her sudden disappearance.

[00:00:13]>> In physics, [music] this Well, that's way smarter than me.

[00:00:17]>> Thanks.

[00:00:18]>> There's two mind processes going on. One to trick, one to trap.

[00:00:21]>> If he were [music] truly innocent, he would be more assertive. Like, what are you driving at?

[00:00:26]>> A battle of intelligence ensues. But when the physics master makes earth-shattering allegations.

[00:00:32]>> Just putting it out there. Just in case something happens to Yingying Zhang in my case.

[00:00:34]>> He trusted her with his biggest secret.

[00:00:37]>> Can he defy the laws of justice?

[00:00:39]>> Why would I lie?

[00:00:40]>> You didn't say that >> [music] >> either way.

[00:00:42]>> There is no way.

[00:00:44]>> Just like Mom, Cody, and Dad love you. Nobody will love you any more or any less.

[00:00:49]>> I'm telling you right now, I do not think you're a murderer.

[00:00:53]>> I don't think that you're a murderer.

[00:00:55]>> I don't think that you're a bad person.

[00:00:57]>> But something got out of control, and we need to know where she's at.

[00:01:00]>> All I want from you >> is a reasonable >> came to help >> On June 9, 2017, Yingying Zhang sends a text saying that she'll be late for an appointment to sign a lease. As the hours pass, she never arrives, and no one can find her.

[00:01:26]A missing person's case is ignited, and within a week, Brendt Allen Christensen is brought in for questioning under the suspicion that he is the last one to have seen her.

[00:01:36]>> Change your plan.

[00:01:39]>> Right off the bat, there's several things that caught my eye in this. One is this is a room where you in all probability interview various witnesses.

[00:01:47]This would not be a prime room to do a suspect or a person of interest. You've got chairs on wheels and the suspect.

[00:01:54]Not a a idea. You've got a distract-of chair here, which I'm not even sure what it is. You have a telephone. Unless it's been cut off, it could ring. I believe distracting [music] someone of this nature with all of these side issues, there's so many things in this setup initially that would say this isn't going to go good in my opinion unless they get lucky.

[00:02:16]>> Well, I'm just wondering if whether [music] the presence of the campus policeman who is dressed much more informally, who shook hands with him, whether this is a basic setup for the good cop bad cop interrogation. [music] >> I'm thinking this is likely due to a lack of resources. How often do you have an FBI agent visiting a campus to do an interview? Not often, [music] not likely. I think if this room was set up properly, you would not have the distractions. The chairs, if they were adjustable, would have been set up prior [music] to the interview being conducted. But, there's a lot going on here that's definitely unusual. But, I think [music] due to the nature of the case, given that this is an international student, and that this is probably gaining a lot of attention from all [music] sorts of angles, uh they may have just not had the resources for an interview at that point in time. [music] >> Another unusual element to this interrogation is the interview team. One is from the FBI. The other is campus police.

[00:03:12]>> Our investigation as I told you probably told you is this appearance of this woman, this young lady, and the most viable tip that we had referred to a black Saturn Astra.

[00:03:25]Um so, uh that's why he came and talked to you >> Yeah.

[00:03:30]>> the other day. Um do you remember what you told him? And I'm not going to hold you to it if there are certain details you might forget.

[00:03:35]>> they came, they were just checking out all of the Saturn Astras in the area.

[00:03:41]>> Mhm.

[00:03:42]>> And then I was pretty rare car, so I would do short lists. Um >> Yeah.

[00:03:47]>> He asked where my wife and I were during I think it was 2:00 or 3:00 on Friday.

[00:03:54]And I mean, I graduated a couple weeks ago, so I'm looking for jobs right now.

[00:03:58]So, I mean I was either playing video games on my computer or watching TV and after that I went out.

[00:04:07]So, I was on a Google personal alloy. I looked into certain things to try and see if I could get some kind of info for an alibi. I sent some texts around that time, but none exactly between 2:00 and 3:00.

[00:04:23]I let them come in the apartments. They searched for stuff. I let them come in the car. They searched for stuff there.

[00:04:31]That's pretty much it.

[00:04:32]>> Okay.

[00:04:33]Uh what did you uh graduate in?

[00:04:35]>> Uh masters in physics.

[00:04:36]>> In physics?

[00:04:37]>> Yes.

[00:04:38]>> Well, that's at least smarter than me.

[00:04:42]>> Thanks.

[00:04:43]>> I can Very interesting comment.

[00:04:47]You're smarter than I am. That is [music] making this guy feel very superior. He's already said, I've checked about my see if I could come up with an alibi, phone did [music] all this. He's giving him what he's done to prove he's innocent. He thinks he's well ahead of the game.

[00:05:04]>> [music] >> And now the FBI guy is playing the you're better than I am role. It's interesting to see how this is going to play out.

[00:05:10]>> I think it's interesting that this is a person who's in physics, [music] which is not interpersonal relationships. It's dealing with abstract concepts. [music] So, he might be a brilliant person, but it doesn't mean that he's going to be good at the way he deals with [music] people. He's demonstrating to the professional there that he's taking this seriously, >> [music] >> that he's trying to be helpful, that he has nothing to hide, and that he is innocent. [music] >> We have two sayings in police work. One is intelligence doesn't mean you're smart. And the second one is being intelligent doesn't mean you have common sense. So, as police officers, we're basically of the same IQ level, >> [music] >> not as bright as this fellow probably.

[00:05:51]So, we play on those two aspects that maybe he's not smart and maybe he doesn't have common sense.

[00:05:58]>> You said your wife was out of town.

[00:06:00]>> Yes.

[00:06:00]>> The guys mentioned something about Wisconsin. Is that correct? Are you guys originally from there or is it >> Yes.

[00:06:06]>> Okay. Um do you know what day she was in Wisconsin?

[00:06:10]>> Um like late Thursday night early Friday morning until Sunday.

[00:06:16]>> Cool.

[00:06:17]>> All right.

[00:06:17]>> Why am I under suspicion? Is it my car or is there anything else?

[00:06:22]>> The suspect asking questions like that is a hallmark of these interrogations.

[00:06:28]He's asking what do you know, right? And we see that quite often. In his mind, in the suspect's mind, he's thinking, well, the car is the only thing they have linked between me [music] and this potential.

[00:06:39]But I want to know what what more do they have? Did I not clean my car [music] enough? Is there other evidence maybe I didn't think about?

[00:06:46]>> He's fishing, like you said. So, that [music] question is so key to a suspect starting to be afraid. They know I was in the car, they seen me on the video.

[00:06:54]He wants to know, do you have DNA? Is there another witness? He wants them to make the mistake. They're not going to.

[00:07:01]>> What other vehicles do you guys own? You own a >> a 2000 Camaro as well. That's right.

[00:07:05]>> Is that one primarily yours or was >> It's primarily mine.

[00:07:09]>> Okay.

[00:07:09]>> So, I'll just be driving the Camaro um the vast majority of the time. When I'm doing errands, I'll take the sedan because it's >> Yeah, probably better trunk space.

[00:07:18]>> Exactly.

[00:07:20]Yeah, but the Camaro's the personal one.

[00:07:25]>> Um >> [music] >> This pause is extremely interesting. It could be part of the plan or could be a new plan. But that, what I call pregnant pause, is on purpose. There's a reason for that, whether it's spark the agent to think something or it's to make this guy think while he's deciding whether he should tell me about this other evidence. There's two mind processes going on here at the same time. One to trick, one to trap. Who's going [music] to win?

[00:08:02]>> In interrogating or interviewing someone, we would arrange for the pregnant pause. [music] And the person who feels the most anxiety is the one who breaks the silence.

[00:08:12]>> Yes.

[00:08:13]>> So, [music] the FBI, looks like he's fumbling around not knowing what to ask next, creates tension. So, it should be interesting to see [music] how this goes forward.

[00:08:24]Roll the tape.

[00:08:26]>> Now, let's let's talk specifically about Friday.

[00:08:30]Okay. You went to school for how long at the U of I?

[00:08:33]>> Since 2013.

[00:08:34]>> Since 2013. So, you're very familiar with our campus.

[00:08:38]>> Not really. I never really um talked to anyone.

[00:08:43]So.

[00:08:43]>> So, you're kind of a loner?

[00:08:46]>> Yeah.

[00:08:47]>> Specifically on that day, okay. Well, you you originally told the agents that came to your apartment that you just played video games all day long. You didn't leave your apartment.

[00:08:56]>> Yeah.

[00:08:59]>> But it's fair to say that we know that that's not true.

[00:09:04]Correct?

[00:09:05]>> Why would I lie?

[00:09:07]>> That approach of why would I lie, again, fishing for more information. He's suggesting that he's this innocent person.

[00:09:14]>> [music] >> Yes, he's aware that the questions that are being asked by the campus policeman is really drawing him closer and closer into the situation. And now he's asking them, "Please supply me with what my motivation would be to lie about this thing." I find it interesting that [music] the silence that we talked about before was broken by the campus policeman who is now taking a more assertive role in terms of dealing with this fellow.

[00:09:42]>> It could be the beginning of the good guy bad guy interview, but it also might be giving the FBI a chance to monitor him without him looking at him.

[00:09:52]So, he's now brought out and it's I believe it's intentional. We know more than you do.

[00:09:57]That's the first step of starting to find out if he's going to break. And I think this question [music] is going to cause him to spin the story again. He's going to have to come up with why do you know more than you're saying? This guy [music] wants to know what you know before I answer. It's going to be interesting to see how they get it out of him.

[00:10:15]>> Brendt Allen Christensen is being questioned in relation to the disappearance of Yingying Zhang. The last time she is seen is when cameras catch her getting into Brendt's vehicle.

[00:10:26]>> I've got her getting into your car.

[00:10:30]I need to know why. This >> Brendt, I need I need to know why she's getting in your car and I need to know where she went.

[00:10:37]>> If we can help her, we need to know now.

[00:10:40]Because we need we need to move on from this.

[00:10:42]>> It It's been like 6 days now.

[00:10:45]I don't accept Sorry.

[00:10:48]>> And you're telling me that I didn't see you driving your car on Goodwin.

[00:10:55]That I didn't see you driving down Wright Street and turning on right in front of parking where everybody pays their tickets and driving down University to Goodwin.

[00:11:06]>> Key tells of someone who is really thinking about what's happening.

[00:11:11]>> Is it [music] the toe taps?

[00:11:12]>> Is it the foot?

[00:11:13]>> Yeah.

[00:11:14]>> This guy went from totally not moving his feet and now his foot is just going like he's thinking thinking thinking and that is one of the key tells. They can't see it, but if they could see it, they would know that he's starting to get nervous, I think.

[00:11:27]>> Mhm. He's very clearly agitated. The officers [music] are starting to push on him. What you think a reasonable person would do [music] if they were being interviewed and weren't implicated in this crime is they would go, "Look, I really want to help you. I really care."

[00:11:41]He hasn't shown any empathy. [music] He hasn't really shown any emotion.

[00:11:44]>> Yeah, you would think that because they're pushing him directly now, you would think that if he were truly innocent, he would be unhappy about that and be a little bit more assertive.

[00:11:54]Like, "What What What are you driving at?" But, he's not. Again, >> [music] >> the passive tone giving nothing because he has nothing to give. I can't think of a reason is what he's telling [music] that person. And he knows it's not a very good response.

[00:12:07]>> These investigators are pushing the brat to the point where he's going to walk out of the room. They're They're risking that [music] right now cuz they gave him the option to walk. So, they're giving him a lot of things to say, "I am now a suspect." So, if he gets up and walks, he doesn't know what's going on. He can't prove his innocence. [music] He's actually interested in what they have. He's proved that a couple times.

[00:12:31]>> He turned on Clark.

[00:12:34]And we still have cameras.

[00:12:37]>> I've seen the videos. I didn't see you.

[00:12:41]>> You've seen what we've allowed you to see.

[00:12:44]>> Yeah, I've seen the stuff that you're talking about.

[00:12:47]>> Do you think that we brought you up here to show you video?

[00:12:52]We want to We want to understand why you did it.

[00:12:55]>> Yeah.

[00:12:56]>> We want to understand why you stopped to pick her up. Was it to give her a ride?

[00:13:00]Are you afraid to tell us that you gave her a ride? Maybe you wanted to make a couple bucks as an Uber driver and she told you, "I had to go get I had to go sign a lease at One North."

[00:13:09]And you're like, "Oh, I know where that's at. I'll drop you off." If you're afraid to tell us that you gave her a ride someplace, we can work with you there.

[00:13:19]>> Again, we're seeing the suspect asking, "What do you have?" Right? It's a very I don't think we've seen it to this extent before where he's going, "Look, I I've seen the video and I didn't see me." He's saying, "I I I saw stuff, but I watched not because I cared about the case. I watched because I wanted to make sure I wasn't in those videos. You can't tell that it's me."

[00:13:40]>> Great response by the uh campus police officer. I have to give him [music] credit. He's basically fighting back with Yeah, we got you on the tape. I just didn't show you on there. And now giving him [music] options. They're starting to give him or you did would you want to make money as an Uber? Did you want to do this?

[00:13:56]Seeing tail bite. He's He's going to have to bite on something because [music] he in his mind knows they've got me somehow in this car with her. I have to now come back with a reason. They're hoping he bites on that. [music] That's the next step. Every little stepping stone is on the ladder to guilt.

[00:14:13]>> But I know that you picked her up.

[00:14:16]I know you did.

[00:14:18]I saw you in your shirt, arms fully extended.

[00:14:24]Where did you drop her off at? She was looking for a ride. She had missed her bus.

[00:14:28]She told you she was going to 1 North, so where did you drop her off at?

[00:14:31]>> I didn't even have my Facebook stuff up.

[00:14:33]>> Okay.

[00:14:36]>> I'm here.

[00:14:37]I was driving on the street again.

[00:14:40]I did pick a girl up.

[00:14:41]I don't know where.

[00:14:42]>> Okay.

[00:14:44]>> I saw her picture. I don't think it was her though.

[00:14:46]>> Do you remember the girl's name that you picked up?

[00:14:48]>> No, she was speaking very broken English.

[00:14:52]>> Tell us about what happened. What time of day was that?

[00:14:55]>> Early afternoon. I don't really remember.

[00:14:57]>> Okay.

[00:14:58]>> I was just driving around.

[00:15:00]Um I saw a girl and she was very distressed.

[00:15:05]>> Let's address the FBI in the room.

[00:15:06]>> Oh, no. Okay. Yeah, the white elephant in the room, the FBI agent.

[00:15:10]>> It's interesting that the campus police officer [music] is the one that's saying, "Look, we have these resources.

[00:15:15]We have this power. We have this control." The FBI agent is just [music] sitting there quiet. They don't have to say that, but we know there's a lot of uh there are a lot of resources being [music] poured into this this case and rightly so.

[00:15:26]>> The campus police officer is doing a very good job right now. I I have to give him kudos for the push. FBI agents letting him carry on and do it. But the FBI are just sitting there waiting for their moment and they have a massive capability coming behind that this fellow does not realize is going to happen.

[00:15:44]>> they really pointed out. Here's what you're up against. We have resources and [music] we'll be all over it. So, he's really turning the heat on him.

[00:15:52]>> The minute the FBI step onto a crime scene, [music] you're activating a national database of everything they can throw at you and money's no object.

[00:16:01]>> I saw a girl and she was very distressed.

[00:16:05]>> Okay.

[00:16:06]>> So, I stopped my car and looked at her.

[00:16:09]I started seeing her and talked to her for a little bit.

[00:16:14]I gave her a short ride. I was going to street out got out.

[00:16:19]>> Okay.

[00:16:19]>> That's all right.

[00:16:20]>> Now, you can see that he's stressed.

[00:16:22][music] He's breathy. You can see that his his body language has changed.

[00:16:27]>> back and forth.

[00:16:28]>> shaking. He's obviously agitated.

[00:16:29][music] He's also hiding his hands.

[00:16:31]Hands can be a really big tell.

[00:16:33]Suddenly, he's quite literally and figuratively hiding something. [music] So, he's giving us more information when pushed, which shows that if they do continue pushing, he's going to continue providing [music] more information at this point. But, he's definitely not giving us the whole story.

[00:16:47]>> And not only is he hiding [music] his hands, but the volume is down. So, he is really shutting down and just leaking [music] out as much information as is required.

[00:16:59]>> On a gradual scale, [music] he said I was home playing video games and this is what you're observing as the police officer now. Now, I was out and I picked up a girl and I she was distressed.

[00:17:09][music] He's slowly moving back to the incident time frame step by step in his own mind. I have to give them something.

[00:17:16]This has nothing to do with the truth right now. He's just buying time [music] and they're slowly convincing him we have more than you know. He's going to come [music] up with some alternative time frame where he picked up a girl.

[00:17:28]>> And whether he's realized it or not, [music] if you're playing video games, even if it's offline and you're not actively playing online with strangers or with your friends, that's logged. We know that information. [music] So, he may have realized that that wasn't a very strong alibi.

[00:17:41]>> Framing of the incident as an accident.

[00:17:43][music] You didn't mean to, you didn't This is what could have happened. It fell off the track, it went wrong. That [music] is the key part of the training of an interrogator. So, this is why they're doing that. It's a It's just a very strategic [music] part of giving them an excuse, a plausible excuse as to why you would have encountered [music] this person who has been missing for a number of days.

[00:18:03]>> I think the next step that we [music] might see here, too, is okay, so we've put you in the car with her, why? And they're going to be pushing on that reason. Why would you hide this in the first [music] place? What do you have to be ashamed about? The suspect might play this up as, [music] well, once I saw that she was missing, I felt like I might be implicated. I thought [music] I might be in trouble.

[00:18:22]So, I didn't have anything to do with her disappearance, but I did see her that night and I panicked. [music] He could say that. I don't know if that's what we're going to see.

[00:18:29]>> Well, there's a girl in the car.

[00:18:31]>> Yes. [music] >> Yeah.

[00:18:31]>> We've got We've got that. And that's the first brick falling out of the wall.

[00:18:35]>> Mhm.

[00:18:39]>> As the FBI drill into the facts, [music] Brendt's story is already starting to change, but Yingying's location is still a mystery.

[00:18:50]>> Did you let her out by the hospital or by the railroad tracks or where did you let her out at?

[00:18:57]>> I told you it was in the emergency center. Um >> Was it close to where you picked her up?

[00:19:02]>> Yeah, it was relatively close. It was in the rest central area.

[00:19:06]>> Okay.

[00:19:06]>> So, I've never been in that area before.

[00:19:08]I had no reason to.

[00:19:09]>> Okay.

[00:19:12]When you say she freaked out, what did what did she do? Did she Did she start throwing things at you? Did she scratch you? It looks like you have a scratch on your right bicep there. Is that from a >> I scratched myself.

[00:19:24]>> Okay.

[00:19:25]>> Usually you'll see defensive marks in these cases depending on the nature of the situation. If the victim is able to defend themselves in any means, you'll see bite marks, scratch marks, you'll see bruises.

[00:19:35]>> Yeah, like this guy's really searching.

[00:19:37]He may be intelligent, but he's searching for answers that aren't making sense. And they're still looking for a body. They still need that. They don't have it. There will be no resolution to the international piece of this and the university piece of it unless they can come up with how it happened and where she is. [music] So, this has extra status as a police investigation because of who it is. Unfortunately, [music] it does. Brings extra pressures when there's an offshore student. The reputation of the university, international ramifications being a Chinese student, there's a whole gamut of things behind the scenes that have absolutely nothing [music] to do with this case at play.

[00:20:13]>> Do you remember if you went indoors?

[00:20:15]>> I went north for sure.

[00:20:16]>> Okay.

[00:20:17]>> I mean, I know I picked her up at the residence.

[00:20:18]>> Yeah. Okay, so you went north >> that It was relatively close to Loomis.

[00:20:22]>> All right. To To where?

[00:20:23]>> It was relatively close to Loomis and somewhere >> Okay, where did you where did you drop her off at?

[00:20:31]>> There's a residential area, I guess a little north of Loomis.

[00:20:35]Um >> The same street you picked her up from, right?

[00:20:41]>> Yeah, north of that place.

[00:20:43]>> So, that would be Goodwin Avenue that you were on?

[00:20:46]>> Okay.

[00:20:50]>> So, and you're facing north when she gets in the car.

[00:20:54]>> me her phone.

[00:20:56]It was like broken English. She said, "I'm going here."

[00:21:01]>> Mhm. So, she was showing your phone like a maps program?

[00:21:04]>> Yeah.

[00:21:05]>> Okay.

[00:21:05]>> Um and I saw it was north, so I started driving north. She said something like, "Turn left after a couple blocks."

[00:21:14]Maybe she said something else. I guess that's really when she started freaking out.

[00:21:19]And she wanted to get out of the car.

[00:21:25]Get out. Try to pull on the door.

[00:21:28]It was locked cuz the car had auto locks.

[00:21:30]>> Mhm.

[00:21:31]>> I unlocked it and she got out.

[00:21:32]Does it >> Notice the recall now. The detail recall. From I was playing video games all day, I never saw anybody, I didn't do anything to [music] suddenly he's got a chronological list of things that happened. He's [music] got her comments. He's walking down the path to confession is what he's doing. It's coming slow. [music] But they have got him talking. He hasn't incriminated himself and he doesn't think he's going to. But everything he says is either disproven or proven over time. So, >> [music] >> circumstantial evidence he's giving without even knowing it. That's what's happening here.

[00:22:11]>> Do you remember what she was wearing?

[00:22:13]>> No, I don't.

[00:22:16]Um she had a backpack.

[00:22:19]Uh jeans.

[00:22:21]>> Did she have anything um on her head?

[00:22:24]>> Was she wearing sunglasses?

[00:22:26]>> Did she have tennis shoes on or flip-flops?

[00:22:29]>> I didn't notice flip-flops or high heels or anything, so it's probably normal shoes.

[00:22:35]Um >> What was her ethnicity? You said she had trouble speaking English.

[00:22:40]>> She was Asian.

[00:22:41]>> She was Asian.

[00:22:41]>> Asian, okay.

[00:22:43]>> Um >> What was What do you think How old do you think she was?

[00:22:47]Was she Do you think she was a grad student, undergrad?

[00:22:51]Was she somebody >> I guess it was about 20.

[00:22:53]>> Okay.

[00:22:53]>> I guess it was about 20. Um Her hairline ish.

[00:23:00]I don't know. Weird.

[00:23:01]Um I had I have trouble telling Asian people apart from one another.

[00:23:08]Sorry.

[00:23:09]>> Well, you would remember this very specific though because when you pulled up to her, you rolled your window down, she leaned into your car, so you were looking right at her face. So, what did she have on her face?

[00:23:20]What did she have on her head?

[00:23:22]You were looking right at her.

[00:23:25]>> I don't >> You don't remember this?

[00:23:27]>> No, I mean even so, I taught many many semesters here, and a lot of the students are Asian.

[00:23:32]>> Was she wearing glasses?

[00:23:36]Did she have a ball cap on?

[00:23:39]>> She She might have been wearing glasses. I don't remember that.

[00:23:43]>> Interestingly, when he said, "I didn't know what she was [music] wearing. I can't remember." he immediately said a backpack and jeans. And I knew what she wasn't wearing, which suggests what she was wearing on her feet. What I think is interesting here [music] is his comment about not being able to differentiate Asian people. There is research that suggests that if [music] you are someone say who is white, uh you're less likely to be able to differentiate faces of a different ethnicity. So, there is research to actually support what he is saying, and that's something that I wouldn't necessarily discount here. But I think in in this case, he's really looking for any sort of [music] defense he can have as to why it is that he wouldn't remember what someone looks like even if they were to lean right into his window.

[00:24:26]>> It was on Springfield, so This house probably in this area, maybe.

[00:24:33]Yeah, like over here.

[00:24:35]I remember being by the quad.

[00:24:38]>> Do you remember driving by Wright Street where the little Circle K is and the big Beckman Institute that is a landmark on our university?

[00:24:46]>> Um I don't think I drove past Beckman.

[00:24:50]>> [clears throat] >> That doesn't ring a bell.

[00:24:52]I've been to Beckman a couple times, and >> Stop the tape.

[00:24:55]You may wonder why this is important.

[00:24:57]This is again opposite to what happened in all probability. He's giving them a story about the route he went with her and I think they are going to be able to come up with his exact route through the cameras. They know where he went and they seen him. There's don't forget there's municipal cameras in that town as well, not just university. So I think the FBI agent pulled up the map on his [music] phone. Okay, show us where you went. So now he's doing it. They got the verbal. Now they're going to let him do the finger pointing and [music] if he makes mistakes it's good evidence to the contrary and see where it goes when they actually pull out some tech advice here down the road.

[00:25:33]>> She was in my passenger side so I had to go this way.

[00:25:36]>> Mhm. Um again, I was driving around a decent amount beforehand. I don't remember exactly where I was beforehand.

[00:25:42]Yeah, we So you were definitely driving all over campus.

[00:25:45]And you were by yourself and you weren't playing video games all day. So why would you tell us that? Why would you tell the FBI that comes to your house that you were excited?

[00:25:56]>> I don't know that.

[00:25:58]I mix up the days. I mean, I thought I was doing this Saturday.

[00:26:01]>> So what did you think that those two agents were at your house talking to you about when they came over?

[00:26:07]>> Friday.

[00:26:08]That's why. I mean >> Friday is a day or Friday or they were there to ask you if you picked up an Asian female and gave her a ride.

[00:26:17]>> About Friday. I mean, they were asking me about Friday between 2:00 and 3:00.

[00:26:21]So I told them I mean, maybe I got my days mixed up.

[00:26:26]You know, I said a little bit ago, I thought I was doing this Saturday.

[00:26:29]>> But you didn't bother to tell them, well, I didn't I played video games all day Friday, uh detective, but I actually did pick up a female on Saturday. You You didn't feel the need to give them that information?

[00:26:41]And it might be important?

[00:26:43]>> [clears throat] >> I mean >> You mentioned your wife went on a vacation with another friend.

[00:26:51]Um you mentioned that there's another guy she hangs out with. You mentioned there's another girl you hang out with.

[00:26:56]Do you guys have a >> We're in a We're in an open relationship. Okay. I have a girlfriend, she has a girlfriend as well.

[00:27:02]>> Okay.

[00:27:02]>> Um, I'm strange between us as well.

[00:27:06]In an unrelated way.

[00:27:08]Okay, so it's not just the marriage, it's just strange.

[00:27:11]So, I mean >> Every marriage goes through some rough patches.

[00:27:15]>> Yeah. Um, yeah. I mean >> How How long's that been going on that that's >> strange?

[00:27:21]Few months. Few months.

[00:27:24]I mean Yeah. I mean, I didn't tell her that I This was I was scared that I mean I'm great now that this is happening.

[00:27:33]You didn't tell her that?

[00:27:35]>> Does she go to Wisconsin with the boy or another girlfriend?

[00:27:39]>> Guy.

[00:27:40]>> How did that make you feel when she went away for the weekend, this long weekend with that guy?

[00:27:48]>> Normal.

[00:27:49]>> Yeah.

[00:27:51]And it's okay. Those that those are normal human feelings.

[00:27:54]>> Yeah.

[00:27:55]>> And did you feel hurt?

[00:27:57]>> Well, yeah, but I mean, she didn't seem to care for a while.

[00:28:01]>> But still, she's your wife and it's tough, you know, even if you're in an open relationship.

[00:28:07]>> The officer is framing the open relationship as something that occurred because of a rough [music] patch, which is a really interesting thing to play into here. There's a lot of interesting relationship dynamics in an open [music] relationship. Certainly, open relationships don't necessarily happen out of >> [music] >> rough patches. People can be in in happy, loving ones, but they're characterized by open communication. The suspect seemed to suggest that when something goes wrong, he hides things [music] from his wife.

[00:28:31]>> Yes.

[00:28:32]>> He hides information. And we're seeing that play out here. He's afraid of something, so he's not telling the officers all of that information.

[00:28:40][music] >> And he's also telling us that he's open to reaching out to other people when his needs are not met.

[00:28:47]Hence, the open [music] relationship, hence the opportunity to reach out to some Asian person appearing lost and vulnerable on the side of the road.

[00:28:57][music] So, he's telling us a lot about himself, his value system, and how he feels, [music] which can create the motive at some point. Okay, roll the tape.

[00:29:09]>> We have 600 Chinese students that have volunteered to look for her.

[00:29:15]What I can tell you is that we will find her.

[00:29:19]Now, when we find her >> [music] >> is up to you.

[00:29:22]But, if you maintain that she just got out of the car and walked away, it's very difficult for us to move forward.

[00:29:31]>> Were Were you hoping for just kind of like a quick trist with her or you see if she you know try to try to pick her out?

[00:29:40]>> You know, it would've been nice.

[00:29:41]>> Do Do you have I'm going to ask you a weird question and you know, a lot of us have fetishes.

[00:29:47]How would you describe your relationship with your wife?

[00:29:52]Are you guys into certain things? Do you like porn? Do you like >> There we go. So, now he's asking about the dynamics of the relationship, specifically about his sexuality, which I think is a is an interesting direction to go with that. He didn't start broad, he's going right [music] to the point.

[00:30:06]He's implying that there's some sort of a fetish going on here.

[00:30:11]>> Notice the number of Chinese students that were going to help with the search.

[00:30:14]Now, if he did not [music] dispose of that body in the proper manner, there's a risk they will find it. So, he's thinking about, "Oh, they're going to do a massive search. They're going to look in every garbage can, every nook and corner of this area."

[00:30:26]>> [music] >> Did he do due diligence at the time of the killing? He's thinking that [music] now, and it'll be interesting to see how it comes back, cuz he's running this through his mind. What's the chances of them finding that body? [music] And if he thinks there's a chance, he's going to start cooperating.

[00:30:42]>> You have to know, you're a smart man.

[00:30:45]You have a PhD, right?

[00:30:47]>> Masters.

[00:30:48]>> You're still a smart man, is my point.

[00:30:51]So, you have to understand how technology works.

[00:30:55]How did you think I knew that she Googled the address to One North? How do you think I knew that?

[00:31:01]1 minute after getting in your car, how do you think I knew that?

[00:31:05]We know that you didn't She didn't get out of your car.

[00:31:10]You need to be honest with us. Help us put this to rest. Help us bring her back to her family. You can do that.

[00:31:18]You can do that. You can do it right now.

[00:31:21]>> This guy has to feel they're closing in on him, but [music] he's being stoic.

[00:31:24]He's not saying I dropped her off. No, we know you didn't let her out of your car. So, they're starting to give [music] bits of evidence that he's was looking for earlier. Now, it's coming after he's lied enough to be caught. [music] >> And then he's taking a two-tier approach. We have evidence, we know stuff, at the same time [music] appealing to his sense of guilt or shame.

[00:31:47]>> For the body.

[00:31:48]>> For the body, yeah.

[00:31:49]The parents, the family. Wouldn't you Do you have a sister? Can [music] you empathize with these people?

[00:31:56]>> Seeing what what might trigger him to say, "Okay, I can tell you where the body is."

[00:32:00]>> And I think once they get [music] a hit, that's where they'll focus their attention.

[00:32:04]>> mother, they'll do everything they can to try to get him somehow to say yes.

[00:32:11]>> The FBI are investigating the disappearance of Yingying Zhang and bring in Brendt Allen Christensen for questioning. While they have begun pressing harder for answers, Brendt has yet to confess to any involvement or knowledge of where Yingying could be.

[00:32:26]>> The second interview is now completely different, obviously. They brought in two different investigators. They have an array of material in front of them.

[00:32:35]This would cause this person to think, what have they got written down there?

[00:32:38]What's it all this stuff they have in front of them? Notice how he's staring down at the papers. He's trying to see what they have in front of them. And these two different interviewers, one of them is dressed in very similar attire to the campus police officer who was in the first interview, probably to give this guy a sense of comfort. Why they've moved the two new people, it's obviously some possible technological issues have come in, maybe a different level of expertise by the interviewers, or they felt they had got enough using their approach and these two guys [music] are going to use a different approach on him.

[00:33:15]>> But they've demonstrated that they have unlimited resources, so they bring in the second team. They might even have a third team, [music] so it's relentless.

[00:33:24]>> I drove through a bunch of residential areas, just um It's more interesting to us, you know.

[00:33:31]>> Yeah, sure. Okay. Okay. Okay. Okay.

[00:33:31]Okay.

[00:33:32]>> It's more interesting cuz all I was doing was driving around, nothing.

[00:33:35]>> So, what?

[00:33:36]>> Yeah, I did that for a while.

[00:33:38]Uh >> How long would you say that you that you drove around?

[00:33:42]>> It's hard to say, a few hours like that.

[00:33:43]>> Okay.

[00:33:44]>> Few hours.

[00:33:45]And yeah, then I saw that girl.

[00:33:49]Uh just waiting.

[00:33:51]And >> Where where were you at when you saw her? Do you do you remember?

[00:33:54]>> On campus approximately.

[00:33:55]>> Near what roads or anything like that that you were >> I was on the north side of campus.

[00:34:00]Um in the engineering part of it.

[00:34:05]I don't remember exactly what street or anything.

[00:34:07]>> Okay.

[00:34:08]>> I was just up there.

[00:34:09]Again, it's all a little bit of a blur.

[00:34:10]Sure.

[00:34:11]>> Sure.

[00:34:11]>> Um So, she got in my car.

[00:34:14]>> Okay.

[00:34:15]>> And I started driving.

[00:34:17]>> Where where'd you go?

[00:34:18]>> North.

[00:34:19]>> [snorts] >> All right. You don't remember the street?

[00:34:21]>> remember the street.

[00:34:22]>> Okay.

[00:34:22]>> Um Yeah, I went north and she got the directions up on her phone.

[00:34:29]She just kind of showed me it.

[00:34:30]It's just a big map. Um didn't really see it that much. Just kind of like flashed it, I guess. Um, and she gave me directions and I assume what happened is I misinterpreted the directions and after after the fact, you know, after all this information was released and where she was going, I did take a wrong turn.

[00:34:49]Um, I don't know whose fault that was. I guess it's not even relevant.

[00:34:52]Um, and she freaked out after that. When she realized we were in the wrong place, she freaked out.

[00:34:59]I don't remember when that was because I wasn't paying that much attention because I was just trying to follow her directions.

[00:35:04]>> What about Tuesday?

[00:35:06]>> Not much happened. Um, cleaned up the Saturn cuz you guys were there last night and realized it was kind of dirty.

[00:35:12]>> He's repeating what they have on video.

[00:35:14]>> I drove through a bunch of residential areas. It's in a residential area. Since you got in my car, I did take a girl up.

[00:35:19]Yeah, I I went north and north of that place.

[00:35:22]>> He's just confirming what they drug out of him in the first interview. He's fast-forwarding it to the point where he can now, hopefully, in his mind, take them on a different direction.

[00:35:32]>> Look at his body position. Look at how engaged he is [music] now. He's leaning forward. He's really soaking up the information. Before, he seemed much more passive, leaning back, hands crossed in a protective mode. Now, he's really leaning in and meeting the interrogator sort of in the middle.

[00:35:51]>> They actually had him use the map function on a phone. They [music] already said that she had used her phone to look up that address. So, that could have been intentional. I would like to think it is intentional that they had him demonstrate that he knows how to use the map function [music] on the phone.

[00:36:06]He's familiar with it. He couldn't have misunderstood. As he just said, he misunderstood [music] what the phone would have been directing him to do and where to go. So, it's just an interesting connection between the first interrogation and [music] what he's saying now.

[00:36:21]>> Roll the tape.

[00:36:23]>> Back in the doubt.

[00:36:24]I took those receipts straight. Uh, there's a there's a car wash and a bunch of vacuums.

[00:36:30]>> Okay.

[00:36:30]>> It's probably like 20 minutes doing it.

[00:36:32]Um something like that.

[00:36:34]Unfortunately, um when I was doing it, I didn't nick my finger. Did I feel it?

[00:36:39]And I did bleed a little bit.

[00:36:41]Um the inside of the car.

[00:36:43]And Michelle told me that there were trace elements of blood in the car. It's mine. It's right there.

[00:36:48]>> Do you remember what you what you nicked it on there or >> No, um that was the annoying part because um I didn't realize I was bleeding until I saw blood in the car and I was [clears throat] like, what is this?

[00:36:59]>> So, you already bled everywhere?

[00:37:01]>> Yeah. And well, when I first noticed it was when I was putting quarters back in the um thing to keep the vacuum going and there was suddenly blood there and I was like, hmm.

[00:37:09]I Yeah, so >> Where was it at in the car? I I >> Um I know there was some on the driver's side. The um thing.

[00:37:20]Uh carpet.

[00:37:22]It's uh I I saw that I had a knowledge of that. That's where I saw Sorry about that. I didn't mean to interrupt.

[00:37:30]>> He is now trying to come up >> [music] >> with the excuse as to why there's blood in the vehicle. Does he not realize that there's going to be DNA? It's going to be his, possibly hers. He's saying it's his blood.

[00:37:41]Yet, in his previous interview, he gave no indication of any amount of bleeding that would have been going on. He said he scratched himself.

[00:37:49]So, obviously there was someone was bleeding more so than a scratch on the arm. Whether it was him or her, but he's actually [music] telling them that there was blood in the car and why it is. It's me. I was bleeding.

[00:38:03]Crazy way to tell what's going on in that car, but he's doing it.

[00:38:06]>> And conveniently, he doesn't know why he was bleeding and [music] realized it after the fact.

[00:38:11]>> He's in a very difficult position and [music] that's why he needs to sell this rather than passively sit back and listen to what they have to say.

[00:38:20]But, it's going to be a tough sell because [music] the chemistry and the science is against him.

[00:38:27]>> Brendt Allen Christensen has been questioned by the FBI multiple times in relation to the disappearance of Yingying Zhang. After these sessions have not brought definitive answers to the case, Brendt's girlfriend wears a recording device to get the evidence they need.

[00:38:43]>> I don't know much about numbers.

[00:38:46]>> Spit it out, you [ __ ] dummy.

[00:38:48]I didn't want to talk about this case.

[00:38:50]I have caught nation's attention. I didn't want to lose what I had.

[00:38:55]I mean it when I say I have a double life.

[00:38:57]>> It amazes you.

[00:38:58]>> It's so strange.

[00:39:00]Just you know what I mean by that together.

[00:39:03]I'm going to continue my work. You know what that means. Cuz I don't have a concrete plan or I'm more successful.

[00:39:12]Reason for all this dumbness in the past that he did. I believe >> Yeah. Brendt, you have fired yourself as the most dangerous person to you. I don't think you'd help hurt Rochelle or I. No.

[00:39:23]>> Rochelle and girl people You're a [ __ ] I trust you. That's the [music] only person we told.

[00:39:31]I tried one night when I was super drunk. I over exaggerated. You showed us the worst me. And the FBI I told them what I might have done. I believe it was true what they told her.

[00:39:42]>> So wait, the stuff that she knows that she thinks was just your drunk rambling was true?

[00:39:47]>> What was >> Do you even know if you saw where she was? How would you >> I'm not going to tell you.

[00:39:52]>> That's fine. You don't have to tell me about any of that.

[00:39:55]>> 20 sniff the eye got more [ __ ] I am apparently very good at this.

[00:40:02]>> You're very intelligent.

[00:40:23]>> Never ceases to amaze me how these things work out.

[00:40:27]To fight so long denying and then to walk into the trial room and have your defense lawyer admit that you did it.

[00:40:34]>> He He viewed [music] his victims as being honored to be >> [music] >> one of his victims. Like many serial killers, this is their idea of a relationship [music] in which they have control. I think that the open marriage and some of the other information we had beforehand lets us know that his [music] interpersonal intimacy issues are not adequately resolved. So he goes and finds people, [music] preys upon them, and feels a sense of control and special. I mean, he was bragging about it. So his demeanor [music] completely changed from the inhibited, nerdy physicist student to a person who has come into his full glory in the image [music] of himself as he has as a controlling, successful person.

[00:41:22]>> Mhm. And it's interesting [music] in that it speaks to the nature of the relationship with his partner. He looks to her as a confidant. He trusts [music] that she's not going to be wearing any sort of wire, but nonetheless, he trusted her with his biggest secret. If we can believe that he's never shared this with anyone.

[00:41:39]>> 90% of the time a woman can bring a guy down. This was done with [music] purpose. It was done because they analyzed him over a long period of time, came up with a a battle plan of what this egotistical [music] monster would break on, and it was a woman.

[00:42:26]>> [music] >> Mhm.