in, they said they heard screams coming from the park. she was found naked and bound with red duck taped. when you see the photos, you can feel the terror. he left her for dead. we were shocked. as a dna laboratory that there were no other offenders. how is this guy not in the system? then, one day, you ve got a call. they said there s been an update on the case. it was like finally. i ve been thinking about who this guy was for so long, i don t think anything could have prepared me for that answer. how do you wrap around mind around the fight that someone you trusted this. i can picture him smirking. a second customization? yes. might screw up. what kind of person does that kind of thing? exceptionally sick, evil. reporter: the evening arrows warm and thick with anticipation. college students, returning a new, mix and drank with young locals. darkness fell on colorado. one more night to take a lusty bite of the flooding summer. that last friday
eric. we were drinking, vodka? yes. what s the next thing that you remember? the next thing i was waking up, with some man on top of me. reporter: but who did this? detective seymour wondered. was it amber s buddy eric? or someone else altogether? the red duck tape, severe beatings, strangulation, like some practiced predator was living out an awful fantasy. i was feeling this intense need to figure out who had done this, and fear for a person out there capable of these things, we need to figure out who this guy is. reporter: what was your level of worry of what could happen in this community if you did not find somebody quickly? i was terrified that he was going to strike again. reporter: coming up the investigation begins.