Cold Case Files (1999)

The Flaming Gorge Falls/Caught in the Mail (3x20)

Air date: May 14, 2001

A man suspected of the cold case murder of his wife and son hatches a new plot to kill his mother and father; and detectives solve the 20-year-old murder of a teenager by tricking her killer into licking an envelope, then extracting DNA from the saliva.