Susan Sarandon, Melissa McCarthy

When Mike & Molly decided to introduce the best-selling author who inspired Molly's new career as a novelist, Melissa McCarthy called one of her favorites to play the role: Oscar winner Susan Sarandon, who guest stars on the November 25 episode of the CBS comedy.

"I hadn't done a sitcom [in front of an audience] since Friends [in 2001], but I thought this would be fun," says Sarandon, who doesn't own a television but recently binge-watched Game of Thrones and Breaking Bad on her computer.

Molly runs into Sarandon's eccentric JC Small in the supermarket and asks the scribe to be her mentor. "But JC's just coming off a bender and is busy loading up her cart with vodka," says Sarandon  — though that doesn't stop Molly from trailing her home. "She begrudgingly takes Molly under her wing because Molly just won't stop following her," says McCarthy, who was recently honored at Elle magazine's Women in Hollywood event.  

The actresses bonded last summer while shooting the upcoming road-trip comedy Tammy, in which Sarandon plays McCarthy's grandmother. "I have swollen cankles and turn out to be a real handful," says Sarandon. "And once again, I'm playing an alcoholic!"

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