Law & Order: Criminal Intent (2001)

S3E4 But not Forgotten

The disappearance of a bookkeeper sends detectives Goren and Eames spiraling back to a case from two years prior involving her hitman brother's murder. Their prime suspect is a jailed mobster who might hold the key to the mystery. However, when a second body is discovered, the investigation escalates, uncovering deeper connections and unforeseen twists.