Cold Case Files

The Family / The Clue That Stuck (4x18)

:

A detective vows not to shave until he solves the murder of a young Oregon woman. It takes three years and a string of Mexican Mafia informants to crack the case and allow the dedicated detective to shave his beard. And in a California case, investigators track down a killer with the help of DNA found on the duct tape used to wrap the murder victim's head.