When a Texas gas store owner, Subir Chatterjee, 58, is shot inside his check cashing booth in 2002, detectives suspect his killer is someone Subir knew. With the murderer's DNA in hand, one detective refuses to retire until the case is solved.

When the battered body of Shawna Yandell, 16, is found floating in Washington State's Yakima River in 1993, detectives first suspect those closest to her. The case grew cold until new DNA technology revealed a callous killer that no one suspected.