The Mentalist Episode 1.08 The Thin Red Line

When a State's witness in a narcotics case and his girlfriend (Patrice Matigan) are shot in a motel room, CBI is called in on this high-stakes case. Local police suspect the drug dealer on trial is behind the murders since there is no case without the witness, but Jane surmises Patrice was the intended target. Focusing on Patrice, the team discovers she might have been having an affair with a veteran police officer, suggesting she was killed by a cop to cover up the affair. But when the evidence doesn't add up, the team stages a fake stake-out to ultimately catch the real killer and uncover the tragic truth behind the murders.