Construction workers discover a skull with bullet hole under the ruins of a disco club burned down in 1978. 22 people died in the fire. Rush and Valens come to the conclusion that the burning of the club was arson, meant to cover up a murder leaving them with not one, but 23 cold cases.
Elenco: Kathryn Morris , John Finn , Tracie Thoms , Jeremy Ratchford , Danny Pino , Thom Barry .