Patrick kills the serial killer nick named Red John in season 6 Episode 8 of the TV Series The Mentalist with episode title:”Red John”
Officer Lisbon and her Team* (with the exception of Patrick) meet with FBI agent Abbott. Abbott tells them that they (the FBI) will be talking to each member of the team over a period of days. During this time Bertram, while stopping at a gas station to call Patrick had an encounter with a police man who identified him. He was shot by Bertram’s accomplice Oscar Cordero. After an unsuccessful raid by the FBI to find Patrick, three members of Lisbon’s Team Rigsby, Cho and Van Pelt met with Lisbon to discuss the ongoing situation. In the following scene Lisbon meets with Patrick at a Park where she tells him about the warrant out for him. Patrick also tells Lisbon about a call he received from Bertram. Bertram called shortly after and ask that he and Patrick meet. Patrick was however cornered by the FBI but managed to escape with the help of Lisbon and her team.
Patrick and Bertram meet at the agreed upon place (which was a church) where Bertram told Patrick about the Blake Association. Bertram also declared that he was not Red John stating that Red John is a top member and he is not. Oscar is then instructed by Bertram to take out (or kill) Patrick, but he is shot instead. The real Red John then reveals himself, and he turns out to be Sheriff Thomas.
During a conversation between the two, Patrick tricks Red John using a Pigeon to frighten him. Patrick takes the opportunity to get the hand gun he hid under the bench in the church and shoots Red John and then his henchman Oscar. At the same time a woman walks in the church seeming to have noble intensions but proved to be one of Red John’s accomplices. Patrick knocks out the woman and Red John then ran in order to escape but he is later caught by Patrick. He was then strangled by Patrick who then called Lisbon (who was being held by the FBI). During the same time an FBI team headed by Abbott arrived on the scene at the church where they found Bertram’s body.
* – Team here refers to the CBI that was closed down by the FBI in the previous episode.