The actress first played con artist Courtney, who scams Charlie Sheen's character out of money, in 2007. McCarthy showed up again last season for a handful of episodes, as Courtney was released from jail and pursued a new relationship with Charlie.
This season, it's been rumored that Courtney shows up to Charlie's funeral. But beyond that, TV Guide Magazine has confirmed that McCarthy's character is also back to stir up more trouble.
With Sheen off the show, it's true that Charlie dies under mysterious circumstances — opening the door for Internet billionaire Walden Schmidt (Ashton Kutcher) to buy his Malibu beach house. Heartbroken Schmidt convinces Alan (Jon Cryer) and son Jake (Angus T. Jones) to stay, but brings his own set of complications — including soon-to-be ex-wife Bridget (Judy Greer).
On the show, Walden winds up meeting Courtney at a bar. Once she realizes his set-up, McCarthy's character tries to seduce him. Alan, knowing her scamming ways, enlists Bridget to help out and save Walden — leading to a showdown between Courtney and Bridget. "How that ends will be revealed in the episode," says a source.
McCarthy isn't the only old flame returning to the show. As Alan continues to navigate his own love life, Courtney Thorne-Smith reprises her role as his significant other, Lyndsey.
McCarthy's recent TV credits include the movie "Santa Baby 2," as well as a guest spot on "Chuck" and a role on the short-lived comedy "In the Motherhood." The ninth season of "Two and a Half Men" premieres on Monday, Sept. 19 at 9/8c on CBS.
To read the first-ever interview with the new "Two and a Half Men" cast, along with creator/executive producer Chuck Lorre's first public comments on the show's reboot, pick up the Fall Preview issue of TV Guide Magazine, on newsstands now.