In an episode called "The Greybar Hotel," Lisbon had to face a dangerous assignment in order to complete a mission.

The last season of The Mentalist saw how Lisbon and Jane try to cover up and hide their relationship in order to maintain a stress-free working environment, and it seems that the pair intend to keep it that way due to the high-wired assignments that the two will engage on.

In the latest episode of The Mentalist, Lisbon had to go to prison for an undercover assignment. Lisbon tries to befriend an inmate and try to turn her against her lover who's the leader of a car theft syndicate.

The beginning of the episode saw how the outlaw couple try to pull a gun on a car they want, with the girl ultimately getting chased by the cops and getting caught. The guy was able to run from the cops, but members of the group tell that his partner, the love of his life, has been arrested.

When Cho and Abbott try to read her charges, they say that her offense would be lighter if she rats on her boyfriend. Naturally, the girl refuses and says that she is willing to go to hell for him, and that jail won't be a problem. The team gets frustrated but thinks of a solution that sends Lisbon to prison to befriend the girl, Marie.

Jane then sends Lisbon off to prison, saying that she will be paired in a cell with Marie and that she should try to find out Cole's location through her. Marie then gives details about Cole one by one, with Lisbon reporting her new-found knowledge to Abbott.