After finding a man bludgeoned to death in the cellar on an empty lot, the team is surprised to discover that the original crime scene is a house on a barge floating down the East River. The victim owned a house relocation company that was moving the house from Staten Island to the Upper East Side. Following autopsy, a torn card stock in the victim's hand leads the CSIs into the world of SecretsU: a website where people send homemade artistic postcards of their darkest secrets for all to see. To catch the killer the CSIs must determine if someone killed the victim to keep their secret from going public or if the victim had a secret of his own that he was killed over.