‘Grey’s‘ spinoff offers hope

Television spinoffs are a tricky business. For every success like “Frasier,” which was birthed by “Cheers,” there’s a “Tortellis” flop of the same lineage.

The “All in the Family” DNA gave us the “Jeffersons” hit – and the “Gloria” disaster.

In recent years, spinning off has been largely replaced by cloning – as with the three “CSI” shows, which replicate the same format but with different casts in other cities.

But tonight, “Grey’s Anatomy,” ABC’s celebrated medical soap opera, is going old school: The pilot of its presumptive spinoff, starring Kate Walsh as the popular character Addison Montgomery, is embedded within a two-hour episode of the show.

Half of it is a regular episode filled with love triangles, wedding dilemmas and medical crises; the other half will establish Addison’s new world by jettisoning her from the show’s Seattle hospital backdrop into a Los Angeles full of old friends and fraught relationships.

Shonda Rhimes, the obsessively secretive creator of “Grey’s,” has let few plot details leak, but the new show’s cast members – Taye Diggs, Amy Brenneman, Merrin Dungey and Tim Daly – will make their first appearances tonight.

Rumored to be titled “Private Practice,” it still must vie for a place on ABC’s fall schedule, which the network will announce in mid-May. But considering that “Grey’s” is ABC’s top-rated scripted show, the spinoff stands a good chance of becoming a series.

The opportunity represents a big leap forward for Walsh, 39.

“I’ve been very fortunate to be a working actress who hovered along,” she says. “And then it was like, boom, ‘Grey’s.’ “

Earlier this season, before Walsh knew a plot was brewing to create a show with Addison at the center of it, she sometimes wondered why her character was still on “Grey’s” at all.

Addison had been introduced to the show’s heroine, Meredith Grey (Ellen Pompeo), and its audience in the last moments of the first season’s finale. A neonatal surgeon sophisticate and a snoot, she was the estranged wife of Meredith’s boyfriend, Derek Shepherd (Patrick Dempsey) – aka “McDreamy” – and she was there to get him back.

Throughout Season 2, the romantic triangle became a quadrangle and later a pentagon, with the introduction of Mark, aka McSteamy (Eric Dane), and McVet (Chris O’Donnell). But eventually, Meredith and Derek got back together and Addison – who, by last year at this time, had charmed fans with her vulnerability and sense of humor – was left by herself.

“She’s done with Derek. she’s done with Mark. Why is she still in Seattle? Wouldn’t she go back to New York?” Walsh remembers wondering.

She laughs and adds: “I never asked too much, because I really love workin’. So I don’t care if she’s there to paint the OB/GYN ward eight times a year.”

Says Rhimes: “Honestly, I feel like Kate’s performance had a lot to do with us realizing that there were so many more places for us to take this character.

“She’s funny, and she could do the serious stuff really well, and she was so strong as a doctor, yet we felt that there was a warmth underneath everything that was happening.”

Walsh, who was born in San Jose, Calif., went to high school in Tucson, Ariz., then moved to Chicago and later New York to do theater.

She’s had a lot of near-misses in her acting career: “In New York, I’d be, like, ‘This is it, man – I’ve got it now!’ And then I would collect unemployment. And waitress.”

A recurring role on “The Drew Carey Show” brought her to L.A., followed by a part on the not-long-for-this-world “Mike O’Malley Show.”

All the false starts have left her with a sense of gratitude regarding “Grey’s,” Walsh says.

“I feel really fortunate to be in my 30s and be, like, ‘Oh, I get it – I get how rare this is,’ ” she says.

With the explosion of fame has come increased scrutiny of Walsh’s private life, as well as uncomfortable queries about the well-publicized troubles at “Grey’s” this season, including the rumor that other members of the cast were jealous that she would be the star of the spinoff.

“Absolutely not. Not that I know of,” Walsh insists. “Everyone has been truly, truly supportive and lovely.

“Literally every person, when they let the cast know I was going to be doing this, every single cast member called me and said, ‘Congratulations.’ “

Strephen McPherson, ABC’s entertainment president, says the spinoff is a risk that is “pretty well calculated.”

“We would have veered away from developing the idea if we all weren’t on the same page,” he says. “We know it’s going to be a good piece. Hit shows are lightning in a bottle, so where it’s going to go from here, who knows?”

Adds Rhimes: “I think the only way for us to wrap our minds around this is just to think about it as a separate entity. We’re not making ‘Grey’s, Part 2,’ or ‘Grey’s: The New Class’ or whatever – ‘Grey’s Anatomy: SVU.’

“The thing that stays the same for me are the themes that matter to me. ‘Grey’s‘ is about a group of strangers who make a family and become friends. That’s the underpinning for me of the show. Part of the underpinnings for this new show are six people who were friends first, then started working together and that makes them an even tighter family.”

Walsh, who is “terrified but thrilled” about the show’s prospects, says she would be “hugely disappointed” were it not picked up, particularly since she doesn’t know, and Rhimes won’t say, whether Addison would simply be incorporated back into “Grey’s.”

But Walsh is confident that Rhimes can strike another chord.

“She’s just got a big mind, man,” Walsh says. “I’m just pitching a little beach umbrella in Shonda’s imagination, like, ‘Ooh, this is great!’ ”