way. she told me it was from a car accident. reporter: larry listened to chris s interviews and caught him talking some of the time about lynsie in the past tense. her hand was pretty much stuck like this. okay. reporter: then larry found something in the paperwork from placentia pd that proved chris had lied to the police early on about his whereabouts on saturday, february 17th, the day lynsie didn t come home. chris had told the cops he stayed close to home. but larry checked chris s credit card statement. there was one entry on february 17th. and it turns out it was santa clarita, which is 50 miles north of where chris lived. reporter: why would chris be in santa clarita? well, that s what i wanted to know. reporter: digging through the reports, larry found information about chris s dad, that he was in construction, and that in
activists. protesters fighting back with molotov cocktails and bows and arrows. now back to dateline. welcome back to dateline extra. i m craig melvin. where was lynsie eckeland? detectives had two possible suspects but no evidence linking either of them to her disappearance. it was time to call in the evidence whisperer. his name is larry montgomery, a detective famous for his ability to spot clues others had missed. here again is josh mankiewicz. reporter: by 2008, lynsie eckeland had been missing for seven years. the case had gone from cold to frozen in time. so placentia pd decided to outsource the investigation to the cold case unit at the orange
nancy, no matter what version of events you believed. and police still weren t telling her anything. nancy, during all this time, feels like she s been sort of cut out of the loop. yes. reporter: like you re not telling her anything, maybe you re not actually working on it. right. reporter: whatever you are doing, you re certainly not sharing it with her. nancy was pretty angry. we worked this case diligently for a long time. at some point you hit the wall. reporter: at the time, there were nine detectives in placentia working everything, drugs, gangs, rapes, murder, and cold cases. by 2008 it was clear placentia pd had hit that wall. they would need help. and who they needed was a guy named larry. tell me about larry. larry is phenomenal. reporter: phenomenal because what, he sees things other cops don t see? phenomenal because he sees
suggestive that what he said, eliminated did. correct. reporter: but when larry compared photos of chris s truck with the photos from the bank, he saw something no one else had noticed. the paint on the back of the side view mirrors on chris s truck was white. what about the truck in the photo? the truck in the photo had a dark spot in that area. whatever mirrors were there, if there were mirrors there, were back. reporter: so it s not the same truck. that s right, it s not. reporter: suddenly chris s alibi had a big hole in it. larry moved on to chris s history with women. two ex-girlfriends talked to police about how chris would become unhinged by rejection or what he called disrespect. larry heard about how chris had once crushed a pet crab with a hammer right in front of one of his girlfriends because he thought the crab had killed one of his fish. this is a guy with some significant anger issues. it certainly appears that
left leg impaired. did she talk about how she became disabled? she brought it up to me and said she was in a car accident and was thrown when she was a little girl. but very matter of fact, not poor me or not anything like that. reporter: but growing up, she needed so much care. her mother nancy was with lynsie like her shadow. somebody had to be with her 24 hours a day. reporter: that was you? yes. it was her and i alone. she was my only purpose. in my life, it was to make her as normal as she could be. reporter: by the time kim met lynsie, her dad and brothers had modify had moved away. kim remembers a tight family unit of just two. how close were they? unbelievably, extremely. reporter: but as lynsie reached adolescence, that started changing. like a lot of teens, she wanted her own identity. she changed the spelling of her