"Happy to be part of the new season of [Shameless] on [Showtime]," the Golden Globe-winning Sagal wrote.
On Friday, Variety confirmed that Sagal will have a recurring role as Ingrid Jones. Frank Gallagher (William H. Macy) meets Ingrid, a crazed psychiatric patient, in an emergency room. Ingrid then becomes Frank's new love interest.
Sagal was not the only star to join Shameless on Friday. Cougar Town star Courteney Cox signed on to guest star in at least one episode as Jen Wagner, a famous actress with a drinking problem. Lip (Jeremy Allen White) is assigned to be Jen's sober companion during her trip to Chicago, but the challenge could be more than Lip can take.
Sagal is a four-time Golden Globe nominee for her role as Peg Bundy on the sitcom Married... With Children. She finally won a Golden Globe in 2011 for her role as Gemma Teller on Sons of Anarchy. She reprised the role for a surprise cameo in the Mayans M.C. pilot, which airs on FX Tuesday, Sept. 4.
Sagal's other credits include Futurama, 8 Simple Rules, Superior Donuts, Brooklyn Nine-Nine, The Bastard Executioner, A To Z, Pitch Perfect 2, Lost and Bleed For This.
After Sagal shared the news of her casting, her fans rushed to Twitter to share their excitement.
"Now I'm even more excited for this season of #Shameless." one fan wrote.
"THE best news to wake up to! i'm so incredibly proud of you and i can't wait to see you on shameless," added another.
"This makes me happy! Katey - Thank you for all the great TV over the years," another fan wrote.
Shameless' ninth season will bring the series up to its 100th episode. The season will also be its longest, featuring 14 episodes split into two parts instead of the regular 12 episodes.
According to the season synopsis, Frank will spend his time campaigning, while Fiona (Emmy Rossum) tries her best to keep her business opportunities growing. Ian (Cameron Monaghan) will also pay the price for his "Gay Jesus" movement.
The first part of the season runs from Sept. 9 to Oct. 21 and the show comes back on Jan. 20.
The first episode, titled "My Penis May Have Helped Heal You," airs on Sunday, Sept. 9 at 9 p.m. ET on Showtime. All eight previous seasons are available on Netflix.
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