Kate Walsh Makes a Surprise House Call to Seattle Grace

“I wouldn’t say it was exactly like ‘coitus interruptus,’” cracks Kate Walsh, aka Dr. Addison Montgomery, about the recent writers’ strike. “But I’d say that when the strike came and stopped Private Practice after only nine episodes, it was like a mad roller-coaster ride when the train suddenly stops: It was disorienting. I mean, you never know what’s gonna happen with a spin-off, and this one had been a dream come true — people were watching it and the network had just picked up our back nine episodes. And then, well… ‘The End.’ ”

What a drama queen! Not only did the unstoppable Walsh use her hiatus to campaign for Barack Obama (“I’m passionately convinced he’s the best person to be the next president,” she says, adding with a laugh, “and that’s not because his wife is a huge Grey’s fan!”). But she did so with the assurance that Private Practice will return with more medical and sexual shenanigans come fall.

And this week, just in time for sweeps, Addison and her dangerously high stilettos are once again clicking down the corridors of Seattle Grace on Grey's Anatomy (Thursdays at 9 pm/ET, ABC). So is she there for a bedside redux with McDreamy, McSteamy or McAlex? “It’s for a very top-secret, important surgery that only she can do,” Walsh says. “Not that I can tell you what that is, because at Grey’s they practically take our fingerprints to guarantee we don’t spill the beans!” (She does admit to “some great, funny scenes between Meredith, Derek and me.”)

Uncharacteristically nervous for a firebrand who had no trouble recently lobbying on Capitol Hill (on behalf of

Planned Parenthood, she pushed for sex-education programs beyond abstinence-only), the actress admits to jitters about returning to the show that made her famous. “Because even when I go back to visit, like my hometown, I worry about that old ‘you can’t ever really go home again’ thing,” she says. “But it was oddly comfortable. It felt like going home in the best way — like, we’re reunited and it feels so good!”

In addition to having “So. Much.Fun!” on set, the actress says that she particularly had a gas hanging with Sara Ramirez (Dr. Callie Torres) and Brooke Smith (Dr. Erica Hahn). “In fact, Sara, Brooke and I started joking that we’d just do another spin-off and call it The Three Bad Bitches in New York.”

Oh, we’d so watch that.

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