In a major shakeup, CBS' sitcom Mom is losing one of its two title characters. Anna Faris will not be returning to the series for its upcoming eighth season, leaving Allison Janney as the sole lead.

The move is surprising. Both Faris and Janney are in the middle of two-year contracts they signed in spring 2019 after lengthy negotiations. Their new deals secured a two-year renewal for the Chuck Lorre comedy through Season 8.

I hear Faris' exit was finalized early into the show's hiatus, and the writers have been writing the new season without her character, Christy. Her absence will be addressed in the upcoming season, which is slated to start production September 14 in Los Angeles.

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'Mom' will go into its eighth season without one of its two leads. Anna Faris is exiting the CBS comedy after seven seasons. Link in bio for the full story.

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`The past seven years on Mom have been some of the most fulfilling and rewarding of my career,` Farris said. `I'm so thankful to Chuck, the writers, and my amazing castmates for creating a truly wonderful work experience. While my journey as Christy has come to an end, allowing me to pursue new opportunities, I'll be watching next season and rooting for my TV family.`

Mom is produced by Chuck Lorre Productions in association with Warner Bros Television. It was created by Lorre, Eddie Gorodetsky and Gemma Baker, who wrote the pilot script on spec. It landed at CBS with a pilot order in December 2012. A couple of weeks later, Faris closed a deal to star in her first full-time TV series role.