The Mentalist: Season 3, Episode 4

3 - 4: Red Carpet Treatment

Jane and the rest of the team investigate the murder of a convict; Henry Dahl, who was later released on DNA evidence. Patrick gets some lessons in inner peace and hunting his adversary (Red John) from the husband of the man's victim. It is ultimately revealed the victim's husband and the husband of an admirer of Dahl both killed him; having conspired to do so (to the point they stole and replaced the DNA evidence initially used to convict Dahl - who was really guilty of his crime, in order to get him out of jail so they could kill him), the former to protect his wife, and the latter to avenge his wife. They avoid prosecution when they point at each other as the killer, and the case is abandoned with some behind-the-scenes effort by Patrick; who receives something from the husband of Dahl's victim to focus his anger on Red John; a gun.