reporter: in the wee small hours of the morning, while the whole wide world is fast asleep, mary bennett is awake. not because she wants to be, but because some things stay with you, whether you want them to or not. and for mary bennett, it s the time 3:40 a.m. every day i wake up around that time. it s embedded in my brain. reporter: for more than two decades, that particular time has stabbed her in the heart, pulled her awake. it s an internal clock, permanently set to the worst day of her life. it began with a phone call, then a knock on the door, and news of something that should never have happened to this family, to this girl. when she would come inside the house, her favorite thing was, i m home. what s for dinner? even if somebody we just finished cleaning the kitchen, she d still ask, what s for dinner? that was cathy. reporter: cathy torrez grew up in placentia a small town nestled amongst the sprawling cities of southern california.
would know he got 20 or 25 pages from cathy, or at least think that. if he s guilty and he killed cathy, he knows those 20 or 25 pages were not from cathy. reporter: that was tell number two. then montgomery noticed how, in his second interview, sam referred to cathy s murder. you know? but then this happened and shoot. he doesn t use the word murder, doesn t say anything like that. it s like, this happened, as if it s small. it s not that big of a deal, it s not horrendous. he doesn t want it to be horrendous because he did it. reporter: tell number three. and then larry caught something else in the interview sam did before cathy s body was found. listen carefully. so you went out with her the saturday before the thursday? right. okay on, and where did you go? in other words a week before she was she disappeared. reporter: did you hear that? a week before she was she disappeared. reporter: before she was. what? dead? murdered?
exactly. reporter: and she s going out with sam. uh-huh. reporter: you marry his older brother. uh-huh. reporter: so that house wasn t just another house on the street. right. reporter: it was family. right. right. reporter: police spoke with members of the lopez family. sam knew cathy the best. how long have you known cathy? jeez, i ve known her for over five years. reporter: they interviewed him down at the station. yeah, i really had fun with her. like i said, that person, i m serious, would always have a smile. we would always be laughing, making jokes. reporter: given their friendship, detectives were curious about what cathy might have shared with sam about albert. since albert tried to commit suicide, she was taking it pretty hard. was she confiding in you? the only thing she mentioned about him was that he hung himself and she was sorry for him doing that, because she thought it was his her fault, okay? that s that s how she said it
and then he looked at my mom, and he said, i m sorry. and all i remember were the flyers that were on my mom s table in the living room and feeling so much pain. i was yelling, not my cathy. not cathy. reporter: mary bennett had been right all along. cathy s toyota corolla had been spotted in a hospital parking lot. a plastic bag was peeking out of the trunk. officers opened it, and cathy torrez was missing no longer. she had been stabbed multiple times. all about the upper chest and neck.
samples, now three years old, to the crime lab. two months later, the phone rang. they had positively identified a fingerprint on the trunk of cathy s car, left there by somebody closing the lid of the trunk. reporter: javier s print was on the trunk of cathy s car? yes. reporter: weeks later, another call from the lab. a bloodstain on the car had tested positive for both cathy s dna and javier s. and the detective found there was something else another major piece of evidence investigators had initially overlooked. when you look at the crime scene photos in the trunk of the car, something jumped out at me. and it just it hit me like i got punched in the face, was there was arterial spurt on the sidewall of the trunk panel. reporter: meaning only one thing cathy was still alive when she was placed in the trunk of the car. so, if javier put her there, he could be charged with murder.