Police catch a break on three cold case murders when emerging DNA technology makes a stunning match: a 73-year-old man who's been in prison since 1993. Detectives interrogate the frail man whose harmless façade is hiding a murderous psychopath.

Once a wife goes missing, her husband becomes the prime suspect when police discover his checkered past. Lacking a body or evidence of foul play, detectives hope to gain a confession from a man they realize might be a cold-blooded psychopath.