>> phenomena. >> they call him the evidence whisper. ♪♪ >> hello. the college student vanished after a night out clubbing. nancy thought she was out sleeping with friends. it would take years for detectives to uncover the truth buried in a pile of lies but could they find lynsie. here is the night lynsie disappears. >> reporter: sometimes the facts are as clear as the southern california skies. other times you have to know where to look to see the truth. this man has made a career of noticing what others do not. >> what's his reputation? >> meticulous investigator. >> pouring over the volume of evidence and finding things that other investigators did not find. the evidence whisperer? >> yep. >> reporter: does this man acts guilty or does he know more than what he's saying? what about this man, can you believe the story he's telling. >> i was supposed to pick her up twice, she was so out of character and did not show up either day. >> reporter: the evidence whisperer were not present on either interview. watching them helps him solve the evidence. >> lynsie was the youngest of three. her mother nancy says he was always there. lynsie had a passion for animals. kim davidson remembers young lynsie has a compassion. >> i was freezing cold and a sweater came up around me and it was lynsie. she gave back in other ways. she struggles with her own disabilities, her left arm was paralyzed and left legs impaired. >> did she talk about how she became disabled? >> she brought it up to me that she was thrown as a little girl, very little. >> reporter: lynsie needed so much care and her mother was with lynsie like a shadow. >> in my life to make her as normal as she could be. >> reporter: by the time kim met lynsie, she remembers a tight family unit of just two. >> reporter: how close were lynsie and nancy? >> as lynsie reached adolescence, she changed the spelling of her name from this to this. after so many years of mom and daughter being each other's best friend, lynsie began to keep something in her life to herself like where she really headed one night in february of 2001. >> reporter: does it make sense she would lie to you of what she's going to do that night? >> i never known her to lie to me but you don't know what you don't know. >> reporter: she told her mom instead of their usual friday night dinner, she was staying with a friend named andrea. someone nancy never met and a young man named chris came to the door to pick lynsie up. >> reporter: she introduced you to this guy named chris. did he say hello to you? >> yes. >> i had a feeling about him. >> reporter: nancy spent so many years worrying about lynsie, it was a struggle to let go but she did. >> the last thing i said was remember your seat belt and she looks over and said back at you mom, love you. >> reporter: nancy locked up the house and went up to bed. the next day lynsie was supposed to call after she was done tutoring two girls from the neighborhood. when the call never came lynsie drove over and found out she was not at her job. >> all of a sudden she was not where she's supposed to be. >> reporter: nancy was frantic. i started calling the hospital and called the morgue, i wanted to see if there is a jane doe in the morgue. >> reporter: there was no jane doe. most people who disappear like that, they come back in a couple of days. >> if not 24 hours, yes. >> reporter: careen lumis, detective of the police department. >> reporter: you checked the e.r.? >> we checked everything. there were no signs as if she vanished. >> reporter: coming up. >> a week ago. >> reporter: when "dateline" continues. n "dateline" continues. when eye allergens attack, the itch can last 24 hours. but with pataday once daily relief extra strength you get fast, 24-hour relief in one drop. make it a pataday with the drop that's right for you. now without a prescription. everywhere. these are real people, not actors, who've got their eczema under control. with less eczema, you can show more skin. so roll up those sleeves. and help heal your skin from within with dupixent. dupixent is the first treatment of its kind that continuously treats moderate-to-severe eczema, or atopic dermatitis, even between flare ups. dupixent is a biologic, and not a cream or steroid. many people taking dupixent saw clear or almost clear skin, and, had significantly less itch. don't use if you're allergic to dupixent. serious allergic reactions can occur, including anaphylaxis, which is severe. tell your doctor about new or worsening eye problems, such as eye pain or vision changes, or a parasitic infection. if you take asthma medicines, don't change or stop them without talking to your doctor. so help heal your skin from within, and talk to your eczema specialist about dupixent. if your financial situation has changed, we may be able to help. i'll be observing your safe-driving abilities. play your cards right, and you could be in for a tasty discount. [ clicks pen] let's roll. hey, check it out. one time i tripped on the sidewalk over here. [ heavy-metal music playing ] -[ snoring ] -and a high of 89 degrees. [ electronic music playing ] ooh! ooh! who just gives away wood? the snapshot app from progressive rewards you for driving safe and driving less. there's an app? -[ chuckles ] beth. -save money with progressive. [ tires screech ] well, that came out of nowhere. advil dual action fights pain 2 ways. it's the first and only fda approved combination of advil plus acetaminophen. advil targets pain. acetaminophen blocks it. advil dual action. fast pain relief that lasts 8 hours. her daughter was missing. nancy ekelund began handing out flyers and counting the days without lynsie. she also went to talk with detective corrine loomis at the police department. nancy wanted corrine to know about her lynsie. nancy always knew where she was. they were best friends. it was a speech corrine loomis heard before. >> it is typical with a lot of parents or family members when they report a missing person, sometimes they give you the idea that this is an idealic family life because if they don't paint a rosey picture that we are not going to be sympathetic to look for them. >> reporter: that you are not going to look hard. they brought in the usual suspects like the boyfriend. >> his name is matthew ramirez, he was at college with lynsie, they had been on and off for a bit. >> when i went over to her house on thursday, she wanted to break up. >> reporter: what was off was soon back on. lynsie and matt were back together in time for the weekend but not in time to make plans for that friday night. >> reporter: then in came the last person to known have seen her, chris mcamis, out of school. he told the cops he was unemployed. lynsie met her from friends about four months prior. chris said that was a lie lynsie made up for her mother. the real plan was to go clubbing all night in san diego. >> she said don't tell my mom we are going to san diego because my mom won't let me go and definitely tell her. >> reporter: when their night of clubbing went bust, they headed home earlier than expected. he dropped off the early girls and headed to lynsie's house. it was after 4:00 a.m. when he got back. lynsie was worried that her mom maher his truck pulled up. that sounded strange to police until they heard from lynsie's friend that other times she had asked to be dropped off right here. >> reporter: chris said he then drove home and police found a photo from a bank atm of what looked like chris' truck heading north on the right street at the right time. to the cops, chris' story added up. that was when police learned matthew and chris were not the only man in lynsie's life. there were someone else. both matthew and chris mentioned to investigators, an older man who drove lynsie around. we heard lynsie referred to him as her friend. >> nancy had no idea lynsie was friends with any older man, she was about to find out. >> reporter: you got a phone call? >> yes. >> you are at your wit's end and the phone rang and it was a guy named marty. >> did you know him? >> no. >> reporter: he said he had money of lynsie that she needed for tuition. none of that made any sense to nancy. after lynsie goes missing. a guy named marty. >> marty rossler. >> reporter: what did he say to her? >> he says he's a friend of lynsie's and he's concerned because he had not heard from her. >> reporter: marty rossler was not marty rossler. he did not have a criminal record. what he did have was a relationship with lynsie that he had not told his wife about. marty was 58 and she was 20. >> reporter: they were boyfriend and girlfriend? >> don't think so. so police brought in marty. over two days they recorded those interviews and at times on videos and at times just on audio tape. >> when was the last time you saw lynsie? >> a week ago. >> no, i don't think so. >> absolutely not. marty said he last seen lynsie the day she went to san diego on that friday. >> reporter: did you believe him? >> we didn't believe him. >> reporter: they received a tip. she seen lynsie with a much older man who matched marty's description together at her store after the day lynsie went missing. >> i was not there on that day. i had been on that store and i am like you, i am easily identified and probably every place i have been with her would know that i was in there with her. >> it was a long interview. >> reporter: friendly? >> no. i remember drilling down on him because i thought he may know where lynsie was. >> reporter: you're a parent? >> yes. >> how many kids do you have? >> two. if you have a child vanished and vaporized in thin air, would your heart not be broken? >> absolutely. >> do you not feel some compassion for nancy? >> unbelievable. i think this is a nice girl and you know this family had a share of hardships. this is just -- i feel so helpless. >> i don't think you are helpless, i think you can help us. >> marty insisted that he could not. detectives were not buying it. >> never touched her. >> have you put her some place where she's left? >> no. >> reporter: police searched marty's home and found nothing. no proof that marty had anything to do with lynsie's disappearance so they move onto a new suspect, someone closer to lynsie than anyone else on earth. "dateline" returns after the break. "dateline" returns after the break. trelegy for copd. ♪ birds flyin' high, you know how i feel. ♪ ♪ breeze drifting on by you know how i feel. ♪ ♪ it's a new dawn... ♪ if you've been taking copd sitting down, it's time to make a stand. start a new day with trelegy. no once-daily copd medicine has the power to treat copd in as many ways as trelegy. with three medicines in one inhaler, trelegy helps people breathe easier and improves lung function. it also helps prevent future flare-ups. trelegy won't replace a rescue inhaler for sudden breathing problems. tell your doctor if you have a heart condition or high blood pressure before taking it. do not take trelegy more than prescribed. trelegy may increase your risk of thrush, pneumonia, and osteoporosis. call your doctor if worsened breathing, chest pain, mouth or tongue swelling, problems urinating, vision changes, or eye pain occur. take a stand and start a new day with trelegy. ask your doctor about once-daily trelegy. and save at trelegy.com. when you switch to xfinity mobile, you're choosing to get connected ask your doctor about once-daily trelegy. to the most reliable network nationwide, now with 5g included. discover how to save up to $300 a year with shared data starting at $15 a month, or get the lowest price for one line of unlimited. come into your local xfinity store to make the most of your mobile experience. you can shop the latest phones, bring your own device, or trade in for extra savings. stop in or book an appointment to shop safely with peace of mind at your local xfinity store. nancy and lynsie had been together. police were not keeping her in the loop. nancy was delighted when they call to say they were coming to visit. >> reporter: you look at the boyfriend and marty, the older guy and relationship nobody knew about. he denies it and you looked at chris. and you look at lynsie's mother? >> we did look at lynsie's mother. we have to. >> i made cookies. >> reporter: the cops were not coming with a coffee. they arrived with a search warrant and shovel and dogs. >> i didn't know what a search warrant was. the house nancy and lynsie once shared was torn apart. i don't know if nancy was on the radar for the long time. it was long enough to be able to set her aside. >> reporter: after that search they did just that. they believe this anguished mother had nothing to do. they took nancy off the list and nancy's boyfriend. he had an alibi putting him some where else at the time lynsie went missing. that left just two. >> i have not seen her since that day, marty, police did not trust because of his secret relationship and he lied about his identity and the man who dropped lynsie off at that quarter. the last person to see her before she vanished. chris mcamis. april 2002, more than a year after lynsie went missing, detectives decided to start over, they brought chris mcamis back to see if his story still held up. >> police turned up the heat. >> reporter: police thought chris seemed oddly calm talking about a calm who may have been murdered. >> if it turns out somebody killed her -- find them. >> reporter: that's as strong as we can get out of him? >> that's as strong as we can get out of him. >> i personally executed. she was my friend, there was nothing. >> reporter: his lack of emotions suggested that chris should move to the top of the list. but, it was not evidence. after the interview chris mcamis was free to leave. detectives were not closer to learn what happened to lynsie ekelund and neither is nancy. you thought one day she would walk back through the door? >> yes. >> reporter: she believed it because she wanted to and because over the years several people have told her they seen lynsie. >> they never saw the front of her face, they saw the back of her and ill held onto every word they said. >> reporter: it was torture for nancy no matter what word of events. >> reporter: nancy feels -- >> nancy was pretty angry, we have worked this case diigently and at some point you hit the wall. >> reporter: at the time nine detectives working on everything, drugs, gangs and cold cases. 2008, detectives pd would hit that wall. they needed larry. >> reporter: tell me about larry. >> he's phenomenal. >> reporter: because he sees things other cops don't see. >> because he sees things, cops don't see. i don't know anybody could have done a better job than larry. >> reporter: the evidence whisper was about to listen to the facts of this case were saying. >> was there something police have missed? you bet. that picture of the truck spotted on the night of the crime, something about it does not seemed right but the evidence whisper is all over it. when "dateline" continues. it. when "dateline" continues. hpv can cause certain cancers when your child grows up. get in its way. hpv can affect males and females... and there's no way to predict who will or won't clear the virus. but you can help protect your child by taking a first step. the cdc recommends hpv vaccination at age 11 or 12 to help protect against certain cancers. hey cancer! not... my... child. don't wait... talk to your child's doctor about hpv vaccination today. before nexium 24hr, anna could only imagine a comfortable night's sleep without frequent heartburn waking her up. now, that dream... . ...is her reality. nexium 24hr stops acid before it starts, for all-day, all-night protection. can you imagine 24 hours without heartburn? for all-day, all-night protection. (man) i'm a verizon engineer, part of the team that built 5g right, the only one from america's most reliable network. we designed our 5g to make the things you do every day better. with 5g nationwide, millions of people can now work, listen, and stream in verizon 5g quality. and in parts of many cities where people can use massive capacity, we have ultra wideband, the fastest 5g in the world. this is the 5g that's built for you. this is 5g built right. only from verizon. psst! psst! allergies don't have to be scary. spraying flonase daily stops your body from overreacting to allergens all season long. psst! psst! you're good. here is what's happening. demonstrators gathered in lieu louisville on saturday to mark one year since breonna taylor's death. astronauts transfers upgrades to the station. now back to "dateline." >> reporter: welcome back to "dateline," i am craig melvin. where was lynsie ekelund? the investigation is at a standstill. enters cold case detective larry. could he uncover many clues that other detectives could have missed? >> reporter: by 2008, lynsie ekelund have been missing for seven years. cold case unit at the orange county da's office to a guy named larry montgomery. with more than 30 years working homicide. larry put away his share of bad guys and not usually by knocking on doors, instead larry works by looking closely at the evidence. he does not work fast. in fact, larry is meticulously slow and that was just what this cold case needed. >> reporter: was there anything in the original investigation that struck you as something you needed to re-examine? >> everything. >> reporter: everything that led police into that wall trying to decide between two suspects. >> i am concerned about this girl and she's missing. >> reporter: marty, lynsie's older friend who kept their relationship a secret and chris. the last person known to have seen lynsie when he dropped her off at that corner. >> reporter: any idea which of those two are a likely suspect? >> no, i don't know until i got into the details. >> reporter: you got reputation of god's in the details. >> reporter: guilty or innocent? was it marty or chris? larry considered another possibility. could it have been random? someone who seen lynsie at just the wrong time? >> so you got a bad guy just waiting and hoping a girl drops out of a car at 4:25 in the morning. >> reporter: it happens. >> and you consider that and you weigh it. is it a good possibility? probably not but still, keep an open mind. >> reporter: larry sat down and read through the entire case file, all the witness statements and interviews. he did that for two years. he watched the february 2001 interview with an unhappy marty. >> reporter: did it strike you as suspicious that marty would call and talk to lynsie's mother and gave a phony name. if you did not know the background of marty then absolutely. >> when i talked to the mother, i just gave an identification. marty rossler. >> which is a lie. >> i don't want my wife to be brought into this thing. >> reporter: larry took a closer look at the idea that marty and lynsie were together at the clothing store after she went missing. >> she was not there on that day. >> reporter: no one found any security video of that and larry learned over the years that well-meaning people often gets dates wrong. marty participated in those early searches for lynsie. >> you eliminated marty quickly? >> yes. marty's behavior matched of not the guilty one. >> reporter: he's searching. larry montgomery turns his attention to chris mcamis, guilty or innocent? >> chris was the last person known to be with lynsie. he told police he discover straight home after dropping lynsie off. he found that photo took him past this atm camera. >> reporter: the video saw that chris was telling the truth and suggested what he said he actually did. when larry compares photos of chris' truck with the photo at the bank, he saw something no one else noticed. the pink on the backside mirror of chris' truck was white. the truck in the photo had a dark spot. whatever mirrors were there, they were black. it is not the same truck.