What's in the silver briefcase?

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That's what fans of The Mentalist are now wondering. Photos are out for "The Silver Briefcase," and it looks like the title object will play a major role in season 7's fifth episode.

Directed by Simon Baker (Patrick Jane) and penned by Jordan Harper ("The Graybar Hotel," "Violets"), "The Silver Briefcase" will see Jane take on a powerful enemy. When a chance encounter with a colonel prompts the faux psychic to investigate the murder of the soldier's wife, the FBI will have to open up a closed case.

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Unfortunately for Jane, it seems the colonel wields quite a bit of influence.

Despite this, new photos show Lisbon, Jane, and the colonel in an interrogation room, all attention focused on a thin silver briefcase. So what is inside? Fans will have to wait until Dec. 28 to find out.

In the meantime, Jane and Lisbon will head to Beirut in "Orange Blossom Ice Cream." Much to Lisbon's chagrin, the pair will have to team up with Erica Flynn (Morena Baccarin). The uncomfortable bit of teamwork will be made even more awkward when Lisbon catches Jane and Erica in a compromising position, one that brings back memories of the time the con managed to seduce Jane (see video below).

Find out more when The Mentalist airs Sundays at 9 p.m. ET on CBS.

Tags: The Mentalist television CBS