Casey Joy News Today : Breaking News, Live Updates & Top Stories | Vimarsana

i'm craig melvin, and i' natalie morales. and this is dateline yeah >> i'm freaking out i walk in, and my sister's not there. her doors open, her lights are on, her bans on done everything was horrible. and i felt it. as >> she had been fearless on the frontlines in iraq >> pretty amazing. i saw her as like, a reall strong soldier >> but something about her terrified at home. we >> i'm scared i don't feel safe. >> a desperate call to police. and then she vanished. when >> something made a prett scared >> yes >> there's no way to say wit that was >> right >> what had happened to this ...

strong soldier. >> but something had her terrified at home. >> i'm scared. i don't feel safe. >> a desperate call to police. and then she vanished. >> something made her pretty scared. >> yes. >> no way to say what that was. >> right. >> what had happened to this beautiful army sergeant? the question would launch a spellbinding mystery. >> you've got a roommate, a boyfriend who she's maybe about to dump. you've got an ex-boyfriend who's suddenly back in her life. >> there were a number of potential suspects, absolutely. >> was a killer out there? >> she was in danger. >> could police...

Called into question. >> that's why we didn't arrest him right away. >> police needed to see exactly what casey joy was doing on those library computers and that would require a very unusual plan. they obtained a search warrant to watch every move made on the computer. this is a recording of casey's actual computer key strokes and mouse clicks. that's casey checking his email. that's casey applying for a job. that's casey typing in how long does it take a body to decay. suspicious maybe but not enough. and then he did this. >> he pulled up a facebook page, show there was gonna be an awareness ...

? >> >> you tell me those, but i don't know anything about it. >> what blood? >> you tell me. >> he tried backing casey into a corner about what might be found in casey's hard drive. >> well we should be able to help you out with that. >> we're hoping he's gonna think to himself everything that they're gonna see they're gonna -- >> were swinging and missing regularly and casey joy was willing to talk repeatedly without an attorney. >> three casey. thank you for cooperating with us. >> he says i've seen this movie and now you're gonna take my fingerprints. he was like a pro.

That morning things weren't right. >> i got a text from casey, at 10 am, and it said her sister didn't come home. it said>> they'd been roommater more than a year now. k.c. felt protective of maribel. he told lucy he had already called police to report her missing. >> orange police -- >> this is not an emergency. i have a roommate. she's 36 years old, and she didn't come home last night. >> so what i did, i texted her at 11:00. i said, happy friday. because we usually text each other anyways. that was my way of connecting. and she didn't text me back. >> unusual? >> yes. >> lucy still wasn't w...