T.R. Knight and Katherine Heigl in Grey's Anatomy by Gale Adler/ABC T.R. Knight and Katherine Heigl in Grey's Anatomy by Gale Adler/ABC

Getting her own time in the spotlight at the Writers Guild Foundation's " Anatomy of a Script" series was guest speaker Shonda Rhimes, creator of ABC's Grey's Anatomy and Private Practice. Prior to taking the stage Tuesday at the Writers Guild of America in Los Angeles, Rhimes gave TV Guide a peek at what's coming up in the final six episodes of this season's Grey's.

According to Rhimes, between split-ups and hookups, the Seattle Grace staff will be riding an emotional roller-coaster. "George and Izzy broke up, and I think they're struggling with what that's going to mean for them in terms of their friendship and where they stand now," says Rhimes. There's drama in store as well for George's jilted ex. "What's going to happen for Callie is really good, really interesting, fairly juicy and I can't tell you a bit of it," teases Rhimes.

One thing fans won't be seeing is Callie linking romantically with the Chief, who still holds a candle for his wife. "People always seem to move on and then they come back," says Rhimes. "We're going to be seeing more of Loretta Devine, definitely."

Cristina will continue to feel the impact of her breakup with Burke. "The last six episodes are going to be her dealing with that loss and what it means for her career," says Rhimes. As for Cristina finding love down the road, Rhimes hints, "I think she's pretty lovable, so in the future, yes."

Also shaking things up will be Addison's return visit to Seattle Grace. "She's going to come in in our [May 1] episode and do some stuff that only Addison can do," says Rhimes. In doing so, Addison's angst is triggered when she learns you can never go home again. "I think we watch her struggle with the difference between who she is in L.A. and who she was in Seattle." Will that struggle land her in the janitor's closet locking lips with McSteamy? Rhimes' allusion to Mark's storyline may be telling: "McSteamy is going to be dealing with that aspect of, 'Is all I am this guy who sleeps around?'"

As for the dynamic duo of Meredith and Derek, Rhimes has already announced that the couple will reunite. That said, don't expect smooth sailing for the relationship. "I think they're going to be happy, but I don't think there's any 'happily ever after,'" says Rhimes. "If Meredith and Derek walked off into the sunset, then that would be it. The show would be over." Bekah Wright

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