A couple spent Memorial Day weekend at the beach, and then they simply vanished. Their clothes and personal items were still in the rented condo, their car was parked outside, and there were no signs of forced entry or foul play. A week later, police would get an unexpected lead from a robbery in progress, and the evidence they found helped solve a crime of unparalleled violence and brutality. Originally aired as Season 13, Episode 46. (thetvdb.com)