mike preadmore: right away, soon as we had it. get flooded with phone calls. we didn't realize how common of a look that actually is. i mean, a lot of people actually look like the sketch. keith morrison: mike williams offered an opinion. it looks like 150 different people that i know. you know, i don't know-- i can take you to a bar right now where everybody in the bar looks like that. keith morrison: but mike told the detectives that a couple of members of a milwaukee band that worked the party looked a bit like the sketch. maybe talk to them, i don't know. maybe she hopped in their tour van and went back to milwaukee. i don't know, she was kind of a free spirit. so i mean, i thought maybe she just cut town, you know? so we sought assistance from the fbi tracking them down, nothing panned out. they all had alibi? yes. keith morrison: but big mike-- neither the detectives nor chelsea's family could shake the idea this guy was hiding something. coming up-- brian sroka: we asked for his consent to search the house, and he denied us

july 2016, 21 months and 1,037 tips after the untimely death of chelsea bruck, detective mike preadmorewhose dna was on her halloween costume. like a patient fisherman, the detective flicked lures around his suspect. so it went, until, calmly and quietly, the detective broke the bad news. for all of daniel's denials, dna doesn't lie, and his dna was on chelsea's costume. and so the question-- how could that be? he was adamant. they kept talking. and then daniel admitted he did have sex with a woman at the party. could it have been chelsea? well, maybe. there's ask. so that means i. that means i. >> asked so, time to reel in the fish. nice. i think i've been pretty a gentleman to you. yeah. really? and you have to me. right. there are some things you haven't told me. all right, but we're getting there, okay? i do not think you're a murderer. i'm being upfront. okay, i'm being honest with you. i've been honest with you 100%. okay. all right. i think something happened. you think something happened. you did not daniel figured detective preadmore must have assumed they found semen dna. so h