How a DNA "detective" helped solve an "unsolvable" Michigan cold case in four days

In February 1987, Terry Wood came home from a night of bowling to discover his wife, Roxanne, dead on the kitchen floor in their home in Niles, Michigan. Detectives say Roxanne Wood had been sexually assaulted and her throat slashed. DNA was preserved from the crime scene, but given technological limitations of the time, there wasn't enough evidence to charge any suspects. The case went cold. Then, 34 years later, investigative genetic genealogist Gabriella Vargas got to work on what had been deemed unsolvable by many because of the scant amount of DNA that was left. TERRY WOOD (police call audio): She is dead, she has been cut. DISPATCHER: Now listen to me, OK? DISPATCHER: I'm going to get some information from you and I'm going to get a car started, OK? DISPATCHER: Don't scream into the phone because the phone distorts, and I can't understand you that well, OK? DET. SGT. JASON BAILEY: You're not in trouble. You're here voluntarily. DET. SGT. JASON BAILEY: That girl look familiar? You ever met her before? PATRICK GILHAM: Nope.  PATRICK GILHAM: This is too much for me man. (Waves his hands in the air, taps hands on table.) PATRICK GILHAM: I gotta talk to my lawyer. PATRICK GILHAM: I gotta talk to my lawyer, man. DETECTIVE: You're under arrest, OK? PATRICK GILHAM: I can't believe I did it — if I did it. But you're saying I did so. PATRICK GILHAM: I'm a monster, man. If I did that, that's a monster. That's a monster, man. DET. SGT. JASON BAILEY: Let me ask you this. How do you think your DNA was found with her? PATRICK GILHAM: I don't remember man, I told you. PATRICK GILHAM: I gotta talk to my lawyer. PATRICK GILHAM: I don't remember man … JANET WOOD (at sentencing): Patrick Gilham is the very definition of a nightmare women fear our whole lives … JANET WOOD (at sentencing): …His actions gave all of us a life sentence, while he got to live his as a free man. … And we are here today to see him finally pay something for what he's done which is likely the rest of his life in a cage like the violent animal that he is. PATRICK GILHAM: I can't believe I did what I did. And I pray for them every night. I am so sorry. I just hope that sometime in the future, with God's help, that they can start to forgive me.

"I believed that this case was extremely solvable," Vargas told "48 Hours" correspondent Peter Van Sant. "I believed that I could solve it." TERRY WOOD: No, get 50 f****** cars started, g*******now!   TERRY WOOD: You mean so you can get a recording on it. PATRICK GILHAM: Nope. Never met her. DET. SGT. JASON BAILEY: Never seen her? Never met her? Don't know who she is? PATRICK GILHAM: I have no clue. BRAD WOODS (at sentencing): It seems like people like him find Jesus in prison, but don't bother looking because the devil will be the only one greeting you.

DISPATCHER: They are started. DISPATCHER: No, I'm trying to get some information from you, OK? DET. SGT. JASON BAILEY: That's a newer picture. Here's an older picture. PATRICK GILHAM: (shakes his head no)  DET. SGT. JASON BAILEY: How do you think?