he was different, he wrote in his sk confessions. he simply could not feel anyone. and so, intentionally or not, he offered a dismal reason for murdering a perfect stranger. it was a single line at the end of that horror movie of his house of cards when the killer tells his wife >> the best way to succeed is to write what you know. this is" this is" someone at a park at 3:00 am. i am andrea kncanning and this is dateline. >> i can't believe she would meet someone at a park at 3:00 a.m. i think she knew the second she got in his car that something was wrong. >> a college student disappears. >> i'd like to have a wellness

check done on my daughter. >> a secret life and covered. >> she was looking for sugar daddies. >> going into it blindly is not something i would recommend. >> chilling details revealed. >> selected her as his victim? >> correct. the bottom of the dig site, there was a damaged iphone. maybe clothing, there was a sinking feeling, really. >> i replay this one night and i went to grab her and say do not do it. do not go. >> hello, and welcome to dateline. college student mackenzie lueck was diving into adulthood, eager to find her path. her family and friends knew her as fun, responsible, and always careful. then, one night she vanished.

a trail of electronic clues helped investigators retrace our steps and exposed a dark underworld where evil was hiding behind webs of lies. here is keith morrison with the waiting car. >> our minds have a curious way of deceiving us. we cents something is off or wrong or even terrible. and yet, something in the brain wants to believe the worst did not happen. kennedy knows that feeling well . >> i was pushing away from mike gut instinct. i am not sure why. i never imagined this ever happening to one of my friends. >> i wouldn't think you would want to imagined. >> or anyone you know. my mind did not go there. >> she told herself it would be

fine as she reached out from her home in salt lake city. messages to her friend mackenzie lueck. >> i saw she was opening my snap chats. i texted her and did not get a text back. this is stupid but i was wondering if she was mad at me for something. >> the mind wants a simple explanation. she knew her best friend was grieving. her grandmother had recently passed away. >> i know she was heartbroken over that. they are all very close. >> she was at the funeral. >> she left utah and went to the funeral. i thought maybe she took a few days of social media. >> mackenzie's parents had not heard from her either. after three days of escalating fear, her dad made that most dreadful phone call to the salt lake city's police department.

>> yeah, i'd like to get, if possible, have a wellness check done on my daughter. i've been trying to get a hold of her and her phone goes to voicemail. i was wondering if somebody could go by her house and check on her? >> the story her dad told was this. on the night of sunday, june 16, 2019, mackenzie boarded a flight from los angeles back to utah, arriving in salt lake city around 1:35 a.m. monday. at 2:01 a.m. she texted her mom to say she landed safely. after that, three days of silence. two patrol officers went to her townhouse. her car was in the driveway. that was a good sign. repeated knocks at the door however went unanswered. peering through a window, the officer saw nothing.

not a soul around. they called mackenzie's dad to report the news. next, the officers found mackenzie's friends, boss, and professors . none of them had seen her. all reasons why by the end of this unsettling day mackenzie's case was referred to a place that sounded serious indeed. the salt lake city police department's homicide squad. >> get a lot of missing person cases in salt lake city. >> lieutenant mitchell was the chief detective. >> i tried to sit through those to find the ones that raise the hair on the back of your neck for lack of a better term and this raised the hair on the back of my neck. i decided we need to take action now and at least start an initial investigation. >> truth be told, most reports are easily resolved. missing person may have lost their phone are decided to take

a break from some family drama. that did not appear to be the case with mackenzie. the relationship she had with her mom and dad would be the envy of most parents. >> they were always contacting each other. they would send silly text back and forth. >> the detectives led the missing persons investigation even though their specialty was murder. >> a usual homicide investigation, there's a dead body. we're starting was something. we are moving backwards and in this case we started with nothing. >> they pulled the airport surveillance camera footage on the night of mackenzie's disappearance. sure enough, there she was. >> it was not out of the ordinary. we saw her come out of the terminal and we followed her to baggage claim she picked up her luggage. >> seemed perfectly normal.

casual. >> nothing out of the ordinary that we could see. >> the last clip shows mackenzie like so many passengers getting into a car outside of baggage claim. the identity of the driver? a mystery. news of the police investigation quickly spread among mackenzie's friends. >> the second i heard about that, my stomach dropped. >> kennedy launched her own investigation. >> i went on facebook. i dropped pictures of us and i said she is missing. if you know anything, reach out to me or police. >> i thought she was still in california until i saw kennedy's message. >> ashley, another one of mackenzie's college friends put a perrone post. >> i take to rent it and because i take her facebook, some of her other family

members reached out to me. >> what family members? >> a distant cousin. one who lives in utah. i said, you know, i have a feeling that she took a lyft share and i feel strongly that she did that. >> you are worried something happened in that car. >> definitely. >> ashley and the cousin called lyft and uber to see if someone it picked up mackenzie at the airport. >> that's when this began because they let it slip, lyft did, that she got in a lyft that night. >> what did you do? >> we contacted law enforcement about the lyft. >> a big break. because it gave them probable cause to serve lyft with a search warrant. >> find out where she was dropped off, what time she was picked up. >> where did she go?

>> we got the destination from the airport to a north salt lake address and she was dropped off at hatch park just before 3:00 a.m.. >> a park at 3:00 a.m.? why would mackenzie come here? just as important, why would a driver leave a young woman alone, burden with luggage at a park in the middle of the night? who would do such a thing? it was the detective's job to track down the driver. who she discovered was not so easy to find. >> is this guy dodging us? >> coming up. mackenzie's friends have a terrorizing -- terrifying theory. >> abducted her. >> here is one reason why. >> her last text message we recovered was at 2:58 prior to her arriving at the location. that was the last activity ever

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a lawsuit against the ride share giant. >> mackenzie's friend imagine something like that or worse. >> i assumed the driver abducted her or maybe they were in a car accident and the car had driven off the road. >> the detectives felt it was a possibility too. they wanted to find that elusive driver who gave mackenzie a ride the night she vanished. >> we wanted to know if he would be a suspect or not. >> he was nowhere to be found. just as odd? mackenzie's phoned the detectives learned was turned off just as her right came to an end. >> her last text message we recovered was at 2:58 prior to her arriving at the hatch park location. that was the last activity ever we had on her phone. >> on the morning of june 22,

six days after mackenzie went missing, the detective finally tracked down mackenzie's lyft driver. >> he said there was not a lot of conversation. he did recall her being on her phone but did not know who she was talking to. >> was a fully cooperative? >> oh, yes. he didn't seem like he had anything to do with this at all. >> because he had an alibi, a very good one actually, as soon as he dropped mackenzie off, surveillance footage captured him leaving to pick up another ride. the date and time and location confirmed by the tracking software on his lyft app . >> he continued that through the night. >> so you could eliminate him pretty easily based on the fact he was elsewhere. >> she was smiling. she was in good spirits. >> mackenzie's lyft driver told police and later us that

he remembered the weird drop off location. even mackenzie commented on that, he said. >> saying how it was odd to be dropped off in the middle of the night at a park. >> he said he wasn't too worried because someone with a car was there waiting for mackenzie. >> i unloaded her luggage and said good-bye and drove away. >> who was this someone in the waiting car? the detectives were hoping they could identify him or her through mackenzie's phone records. and, she had been texting and number with a 206 area code right up to the point her phone went dead. >> we were able to take that number and run it through our database and it came back as absolutely nothing. didn't come back to anybody. >> had to be a burner phone.'s

whoever that was didn't want anyone to know in official capacity. >> it was obvious at that point. >> according to the lyft driver, whoever met mackenzie at the park made no effort to conceal their identity from her. to the contrary. >> he seemed to know each other pretty well. i think all i heard was how are you doing? how was your trip? basic greetings. it seemed very safe. she knew the person that she was getting in the car with. >> did mackenzie caught a ride with someone she knew was good and bad news. the good news is it but maybe mackenzie went off with a friend somewhere. the bad news? because there was no proof of a crime, detectives lost the ability to get additional search warrants. >> we lost our probable cause

that a crime had been committed. just like that. >> because of what the lyft driver said, you can't get warrants? >> correct. that was hard and it slowed the investigation at that point because we didn't have a crime to attach to it. it was still a missing person investigation. >> the detectives were blocked from getting detailed phone records which, theoretically, would have shown who mackenzie was texting. who was this friend mackenzie met at the park ? where did they go? >> investigators are about to uncover fresh clues that deepen the mystery, but also give mackenzie's loved ones a glimmer of hope. coming up. one place mackenzie was not missing was on social media. >> different people saying, i'm looking at her site and it showing she's actively online. >> her bank account was active

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keith morrison (voiceover): so many questions. why did mackenzie go to a park eight miles from home so many questions. why did mackenzie go to a park eight miles from home at 3:00 a.m. no less? who did she meet? it made no sense that her friend ashley. >> i can't believe she would

meet cement at the park at 3:00 a.m. it is so unlike her? >> it is? because mackenzie like most of her sorority sister talked a lot about safety. >> i have been out with her a lot of times. she has always been extremely safe. she has texted me after going out at night and say, did you make it home? are you okay? >> you would exchange things to keep each other safe? >> yes. >> ashley met mckenzie almost four years earlier. >> she was shyer than you would think she would be. she would make anyone laugh. >> kennedy met mckenzie and college. >> her family doesn't live here . she had a job. she was going to school. she was checking off everything that a responsible adult would have on their checklist, i guess.

>> mckenzie grew up near los angeles, el segundo, and she was raised in the church of latter-day saints, but when she came to the university of utah to study kinesiology, according to ashley, she didn't exactly remained about. >> i know she was registered here. i heard she was never active and that made sense to me because i think she wanted to find her own path. >> you saw her changing in recent times? in what ways? >> i think she was trying to almost gain confidence in security intercell bench she would write yourself a note saying how she wanted to feel more confident because i think she realized she was shy and wanted to be more outgoing and meet people. she wanted to explore dating and it might not be how everyone else thinks dating should be.

>> ashley is getting at, mckenzie was active on dating sites. so much so that by june 22, the sixth day after her disappearance, detectives had received several phone calls from some of the men mckenzie met online. mainly to say they had nothing to do with her disappearance. >> nowadays, that's how people meet people. while it was of significance because it gave us one more thing to look at, it was not this huge red flag either. >> was mackenzie on a lark with a guy she met online? a hookup she wanted to keep secret from her devoutly religious parents? that seemed far more likely than a kidnapping scenario. >> she could've gone camping or with a friend where they would lose cell service and it would be out of the ordinary. >> once they did checking

around, the camping idea seemed less likely. standard procedure, they looked up airline flight records and discovered mackenzie had been booked on a flight out of town to las vegas. maybe she was there and meanwhile, the detectives begin to see activity on her bank account and something is. >> different people saying i'm looking at her site and its showing she's actively online. >> maybe she was fine, ignoring the fuss or zoned out entirely unaware. >> we were hopeful. when people go missing, even if it's on their own accord, they are making transactions were paying for stuff. we were hopeful there would be further transactions so we could find her. >> not far from the police station, kennedy and ashley hosted a rally to make sure everyone in salt lake city knew to be looking for mackenzie.

>> this girl is missing and we are looking for her. we think she is in danger. >> but, was she? june 23, detectives learned mackenzie had a flight booked for that day, traveling from las vegas to los angeles. to attend a friend's waiting. >> she would not miss that. we contacted lapd and they had officers waiting for that flight to land. >> they waited for all the passengers to deplane. mackenzie was not among them. then, they learned this. it was not mackenzie who had been logging into her social media accounts. that had been her friends. >> they obtained her email and password and they were not doing it to ruin things. they were trying to monitor the sites as well to see if any information would come up. >> the activity on her bank

account? >> lyft transaction and a automatic payroll deposit from work. >> them the detectives got a tip from this guy. he may be -- bring those blurry details into sharp focus. >> coming up. >> i got on the computer and within an hour, i found her profile. >> the world of sugar babies. >> i think it's more embraced for women to be up front about what they will need and want. >> did mackenzie know what she was getting into?

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i'm richard lui. israel saying they rescued four

hostages during a raid in gaza who had been kidnapped by hamas during the music festival on october 7. officials say more than 200 palestinians were killed by airstrikes nearby marking one of the bloodiest single days and eight months of war. president biden and the first lady attended a state dinner in paris hosted by the french president. he's wrapping up his trip commemorating 80 days since the day. where was mackenzie lueck? welcome back soto dateline. i am andrea canning. where was mackenzie lueck? the college student took a lyft to meet someone at the park at 3:00 a.m., but who? mackenzie was active on dating sites making police wonder for the right -- late night rendezvous was a hookup and radio silence was intentional. a tipster was about to share troubling details about his encounter with mackenzie before she went missing.

here is keith morrison. >> a few weeks before mackenzie lueck vanished, a chance meeting at a bar with this man. rob joseph. >> she seems like a bright, bubbly girl. friendly. >> they talked for more than an hour he said, or she did, while he listened. rob is an ex-salt lake city cop, private i now which he told her. >> if you message your and x copper pi, everyone wants to tell you their dark secrets or risky behaviors. you would be surprised. people want to tell you things you do not want to hear check. >> he only saw mackenzie that one time, he said. did not get her phone number. >> i did not offer my number. >> that was that, he said.

he did not expect to see her again. three weeks later, mackenzie was missing . rob said the friend who was with him at the bar that night made the connection. >> he mentioned, that girl we met at the bar, that's the girl that went missing. >> of course, rob remembered the friendly college student and the secrets she revealed to him that night. >> i don't know if she was seeking approval or advice or recommendation. >> how did she put a? >> she said she was on a dating site and she was looking for sugar daddies. and i said which one? she said seeking arrangement. >> designed to connect young women with prosperous old men. rob no lot about dating sites. he is a pi. he figured if mackenzie was missing, that might have something to do with it. >> i got on the computer and

got done seeking arrangements and within an hour, two hours, i found her profile. >> there she was. beach baby 96. >> what was interesting about her profile is it was authentic and honest. she was a hiding who she was. she was pretty specific, a 23- year-old grad student studying kinesiology. california girl. likes to drink wine and go out and travel. looking for somebody to do that with. >> a little more pg than some of them? >> yeah. >> he sent to screenshot to the police department. >> it was another avenue we had to look at and track down anyone who might've been in contact with her. >> mackenzie it appeared had compartmentalized information about her life. the plane ticket to las vegas had been paid for by a man she

had met through seeking arrangement. a $300 deposit from one of her bank accounts? >> that was from one of her other dates she had been owned that she had received a payment from. that was prior to her going to her grandmother's funeral. >> her friend ashley said she did not have a clue. >> i didn't know anything about her being on this i. >> she didn't talk about it? >> not with me. >> kennedy wanted to avoid the subject altogether but acknowledge the seeking arrangement is well known on campus. >> the site is not unfamiliar to a lot of women in college. everybody knows of this site. >> seeking arrangement was founded in 2006 by a self- proclaimed nerd and mit grad brandon wade. he declined our interview request but in this 2016 "today show" story, he said he came up

with the idea as a way to meet young women. >> the average sugar babies roughly 27 years old. 50% are college students. they are ambitious and beautiful and they are on the website because they want to find someone who is successful it will help them or spoil them. >> we are living in a culture where it's much more accepted and embraced for women to be up front about what they need and want. >> this journalist writes about sex and culture and sees sugar as a form of female empowerment. >> to hold power in a way that's open that is less stigmatized than it has been in the past. >> they see this as holding power? >> i see it as powerful. >> explained that. >> when you go when a relationship saying this is what i need and if you cannot give me this, i will move on, is a powerful thing to say.

>> there is debate about this weather it empowers young women or exploits the innocent. >> i mean, a lot of people who go into it are seriously so blind to the whole reality of what it is. >> like mackenzie, she came from salt lake city and a seeking arrangement profile but unlike mackenzie, she told us she was anything but a newbie when we spoke to her in 2019. at the time, the twentysomething had been with a sugar daddy for six months, and he was 63. do you mind telling me how much he pays you? >> my allowances 1200 a month. >> she said it took her a long time to find an arrangement. >> you have to fish through all the guys who they are like, let's meet at a hotel. have sex until give you money. i said, that's a prostitute.

>> shades of gray can be confusing for anybody she said let alone a novice on seeking arrangement. >> i have seen girls who have had sugar daddies and they're not the same afterward. >> did you read mackenzie's profile? >> yes i did . >> she came from a sheltered upbringing. that made it more dangerous for her? >> most definitely. going into a blindly is not something i would recommend. at all. >> let's talk sugar. this episode is all about getting ready for your sugar date. >> sugar arrangement makes with a call let's talk sugar videos. offer advice to novice sugar babies giving advice and tips on how to ask for an allowance for what to pack in your purpose. perfume they say and pepper spray. >> not that you will need it,

but looking hot is always a risk. >> did mackenzie watch the videos? we do not know. one of her decisions betrayed her lack of experience. >> why would you meet in the middle of the night in a park? >> there was something else whether mackenzie did it or the person she met, we don't know. remember, right after the driver dropped her at the park, someone turned off mackenzie's cell phone which happens to be contrary to seeking arrangement's most important rule. >> never get stuck phoneless. that is your lifeline. >> mackenzie lost her lifeline, but before it went silent, she was busy texting . soon, investigators would follow her digital trail to the elusive man who received those messages. coming up. >> we have an ip address that

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lueck's disappearance was voluntary or not. detectives in salt lake city were trying to find out if mackenzie lueck's disappearance was voluntary or not. remember the flight she was supposed to be on to los angeles? they found out it had been paid for by a sugar daddy. remember, mackenzie was not on the flight. they found out she was not on the one to vegas either. >> it was at that point we were able to say, we have enough we can build probable cause backup and start serving search warrants again. >> off they went in search of the mystery person mackenzie was texting the night she vanished. spent with a 206 area code, conversations going well before she left l.a. to all the way to where she ended up in hatch park. >> the digital trail eventually led them to a wi-fi router at

the salt lake city house. owned by a man named ayoola ajayi . aj, x national guard, successful tech worker, part- time model. police knocked on his door. talked with him and found he was friendly, helpful. sure, he said he had girlfriends but mackenzie? they showed him a photo . >> he said he'd never seen that lady before. >> why, the police asked did mackenzie get texts routed through his home wi-fi system. >> he said i have an open wi-fi because i run an airbnb business. it could be anybody. >> did he run an airbnb? >> he did. he rented it two bedrooms in his basement. >> they looked around and saw nothing amiss and left. then, the same evening, aj stopped by the police station to say he

discovered something. turned out he had texted with mackenzie lueck the night he disappeared. he said he had forgotten because mackenzie reached out to him without identifying herself. ab, he said, she had seen his seeking arrangement profile. >> so, i think that's how she met on my profile. >> she texted your number? >> said he had no idea who it was. >> you are saying that's the only messages you got from her? >> that i can remember. there is a possibility that i've talked to her in the past. >> she blew him off, he said. he forgot all about her. he told that story with so much confidence. too much maybe? >> we had two different things. an ip address to his address

and now we know he has solely contact with her. >> except there was no proof that mackenzie had abducted by aj or anyone else . he was free to leave. before doing so, he gave the detectives his cell phone number in case they needed to get a hold of him. the number actually registered in his name. remember, police did not have that before. they just had the bogus 206 number used by the texting app. now, with his personal cell number, they could get a search warrant for his call records and tracking data. two days later. >> we got the confirmation back that mackenzie's records were showing her going from the airport to hatch park and aj's records were showing going from his residence in meeting up at hatch park at the exact same time. >> that was enough to get a warrant to search his home

where investigators noticed a mattress was missing from the bedroom and there was a strong smell of bleach. they spoke with a concerned neighbor, her face blurred in this police video. wanted the police to know the aj the week before started an will legal backyard trash fire. >> she described it as being offensively smoky and very odorous. >> debris flew into the neighbor's yard. >> it looked like there were clothing, pieces of vinyl or something. >> what was it like when this discovery was made? >> it was a sinking feeling, really. it's like we want to know what happened but we don't want to know what happened. if it's what we think, we don't want to know if that happened if that makes sense. >> coming up. >> that was probably the hardest part was watching him walk out the door that night. >> hard for detectives but it gave mackenzie's friends reason

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powering smarter savings. powering possibilities. welcome back. police finally discovered who mackenzie lueck was texting welcome back. police finally discovered who mackenzie lueck was texting before she went missing. a man who went by aj. he told detectives they never met in person but cell phone

tracking data placed them at the same park at the same time mackenzie vanished. now, investigators were closing in on the suspect, but are they getting closer to answering a crucial question? where was mackenzie? here is keith morrison with the conclusion of the waiting car. >> police looking for mackenzie lueck had heard a disturbing story. from a neighbor who said ayoola ajayi set a suspicious fire . the neighbor had found debris in her backyard. so, they looked in aj's backyard and found something else disturbing. a freshly dug patch of soil. they called in a cadaver dog which gave the unmistakable signal. human remains. aj who had been call me watching from his driveway was taken into custody.

a team from the crime lab spent the night digging up the backyard. >> they found more burned clothing. purses, backpacks and toward the bottom of the dig site, there was a very burnt and damaged iphone. the medical examiner identified human tissue. >> just fragments, mind you. they could not be certain who or even what they had exactly. >> we had these tissue sample or pieces, and so, in order to arrest somebody, that needed to be confirmed. we knew that would take time. >> so, without solid proof a murder had been committed, they reluctantly let aj go. >> that was probably the hardest part was watching him walk out the door that night. >> mackenzie's friends heard he was released and took it as a sign of hope.

>> that maybe mackenzie was alive and he was hiding her. the police let him go the next day. >> then at daybreak, detectives got a call from the state crime lab about the remains found in the backyard. >> they were able to identify that as being consistent with mackenzie. >> the s.w.a.t. team took aj into custody and police called a press conference to arrest his arrest. >> we are filing charges of aggravated murder in the homicide of mackenzie lueck. >> kennedy was watching on her cell phone. >> i almost blacked out or something. i dropped my purse, my phone, and i dropped to the ground on the street. i was bawling. >> i couldn't even believe it. i still can't believe it. >> but the detective's work was not done although they found human tissue in the fire pit

and linked it to mackenzie, they had not found her body. the investigation continued and , once again, aj's personal cell phone gave him away. remember when he first spoke to police about mackenzie? the very next day his cell phone pinged its way up into these mountains. >> two hours north up at logan city and then goes partially up to the canyon then returns back to salt lake city a couple hours later. that was odd to us. >> had he, a nervous killer, exhumed her body from the backyard fire pit and reburied her up.? they set off to search logan canyon. >> it took the better part of the day until we found her. >> that's got to be another tough part of your job. >> it was horrific. it was a sight none of us wanted to see. >> the search for mackenzie was

over. the investigation was not . in the weeks following, a woman came forward to say she had been sexually assaulted by aj a year earlier. >> at his residence, the same or mackenzie was killed. >> she said she met him through dating app, a religious one. aj was charged with aggravated kidnapping enforceable sexually abuse. evidence of what he did to mackenzie was growing . and, finally, october 7, 2020, ayoola ajayi pleaded guilty to murdering mackenzie lueck. as part of the plea deal, he admitted he thought about killing mackenzie and then he planned the killing of mackenzie . a thoroughly premeditated murder. >> he knew he was going to murder mackenzie before she even touched down at the airport. >> he selected her as his

victim? >> correct. >> was there any explanation of what his motivation was? >> he never offered any reasoning of why or even how. >> ajayi pleaded guilty to sexually abusing his first victim. he was sentenced to life without parole. one more thing so the detectives, he was active on the seeking arrangement site right up until he was arrested. >> even after we made contact with them, he was still on that page. still trying to get a date. >> we don't know why. some selfish jerk used his position on a dating website to somehow ensnare this bright, pretty woman, and for what? >> you look at profile pages on

the sites, and he comes across as a gentleman. something he is not. that is the cautionary tale is are they really are who they say they are? >> always, she had been surrounded by people who loved her, worried about her, cared about her. mackenzie lueck was an innocent. setting out if only for a moment to explore new possibilities. unaware that in the world she was centering, the innocent can also be pray. hi'm craig melvin and this is dateline. >> my parents were supposed to help these kids. you would expect this to be a good christian place. no parent would have sent their