Allison Janney Allison Janney

The West Wing's Allison Janney is set to guest-star on the upcoming season of The Big C, Showtime announced Tuesday.

The Emmy-winning actress will play an ultra-successful Hollywood producer who wants to purchase Cathy (Laura Linney) and Paul's life rights in order to tell their story on the big screen. Other notable guest-stars coming this season include Susan Sarandon and Victor Garber.

Pilot Season: Tony Shalhoub, Allison Janney going to NBC's Friday Night Dinner

Janney, whose credits also include ABC's short-lived Mr. Sunshine, recently landed the lead in The Office boss Greg Daniels' adaptation of British comedy Friday Night Dinner.

The Big C will return for its third season on Sunday, April 8 at 9:30/8:30c on Showtime.