S3, E8: Consequences
When a professional paintball player is shot in a warehouse, the team assumes the murder was committed by an opposing player who took the game too far. But their investigation becomes more complicated when his opponent goes missing. The evidence at the scene proves to be "black cocaine" originally confiscated in a raid by the police department months before, and Mac's suspicions of an internal leak causes friction within the department. Meanwhile, Stella grows increasingly paranoid when she suspects that she's being followed.