A reunion that is both anticipated and feared

There’s nothing like a nasty case of worms in the brain to bring a gang back together.

On the set of “Grey’s Anatomy,” a gaggle of doctors have congregated around the hospital bed of one of their own, a neurologist who’s suffering from the life-threatening illness. Dr. Derek Shepherd (Patrick Dempsey) wants to perform risky surgery on the patient (Grant Show), who just happens to be the brother of his ex-wife, Dr. Addison Montgomery (Kate Walsh), who exited “Grey’s” in 2007 for a fresh start on its spinoff, “Private Practice.”

Now, just in time for sweeps, Addison is back at Seattle Grace for the first crossover between the ABC series.

“This is like our ‘Big Chill,’ ” said Shonda Rhimes, who created both soapy medical dramas. “It’s that idea of who you used to be and who you are now.”

The timing of the on-screen mashup, which airs Thursday, is notable as well: “Grey’s” is in the midst of a rocky fifth season, while “Private” is still regarded as its less popular kid sibling. The idea for a crossover was first floated by the network last season but, with “Private” still in its infancy, Rhimes was resistant. “I wanted to solidify the identity of what ‘Private Practice’ is,” Rhimes explained, “both for audiences and in our minds.”

Because of the writers strike, “Private” had precious little time in its first season -- nine episodes, to be exact -- to try to carve out that identity. Echoing some fans’ criticism of those early installments, Suzanne Patmore-Gibbs, executive vice president of drama development, ABC Entertainment, said she thought “we sort of lost sight of Addison as the kick-ass surgeon.” In her place was an Addison who danced around her beachfront home in a towel and flirted with the giddiness of an insecure teen. “We all sort of longed to see some of the swagger return,” Patmore-Gibbs said.

In “Private’s” more grounded second season, a stronger Addison -- and the rest of the docs in the Santa Monica-set practice, including Taye Diggs as Sam and Audra McDonald as Naomi -- have been given meatier medical cases. “I think Shonda has figured out a way to make the medical stories feel like great ethical dilemmas with [high] stakes,” said Patmore-Gibbs, even without the inherent drama of “surgery every three minutes” like on “Grey’s.”

Still, that hasn’t been “Private’s” biggest challenge. Spinoffs often have difficulty establishing themselves as entities separate from the shows that launched them, particularly when that show is as hugely successful and has permeated the pop-culture consciousness as pervasively as “Grey’s.”

Perhaps recognizing this, Rhimes no longer seems as concerned with putting distance between her dramas. In December, ABC moved “Private” from Wednesdays to the post-”Grey’s” slot on Thursdays, something the show runner balked at when the spinoff began but now said she embraced. “There’s something lovely about having that much real estate on Thursday night,” Rhimes said. “I feel like ‘Private’s’ getting a real chance to have a strong show lead into it.”

So far, it seems like a smart move. “Private” now averages 9.4 million viewers, up from the 8.7 million who regularly tuned in on Wednesdays. (“Grey’s” has brought in an average of 15.3 million viewers this season.) Clearly, everyone involved is hoping the crossover will encourage even more of the “Grey’s” audience to stick around. The likelihood is greater, Walsh believes, because the storyline is “more organic than just having everybody from L.A. attend a medical conference in Seattle.”

And boy, how things have changed since Addision worked at Seattle Grace: Her ex-husband is planning to propose to girlfriend Meredith (Ellen Pompeo). Her ex-lover Sloan (Eric Dane) is dating Meredith’s sister, Lexie (Chyler Leigh). And former BFF Callie (Sara Ramirez) is maybe, possibly gay. Said Walsh, who sticks around through the Feb. 19 “Grey’s,” “It’s like going home for the holidays to your crazy family and finding out, ‘Oh, my gosh, that happened? Wait, what?’ ”

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A haunted story line

Many “Grey’s” fans have been similarly incredulous about the drama’s current season. Rhimes began the year by giving viewers exactly what they had long clamored for: The reunion -- this time permanent, she promised -- of notoriously on-and-off couple Meredith and Derek. But in more recent months, another, more controversial coupling -- Izzie Stevens (Katherine Heigl) and her dead former fiance Denny (Jeffrey Dean Morgan) -- has emerged front and center.

To say that the unconventional romance is unpopular would be an understatement. “Enough with the dead Denny/Izzie thing! Ugh!” wrote one poster at The Times’ “Grey’s” Show Tracker blog. Pleaded another, “Can we stick to the somewhat realistic dramas of the characters and the struggles of this profession versus daytime soap crazy stuff like the dead coming back to life and having sex?”

Rhimes said she is acutely aware of the response. “I know the fans wouldn’t have such strong feelings if they weren’t so involved in the show,” she said. “But I also feel like, you start on a path and you have to stay the course.”

She staunchly defended the Izzie-Denny pairing, which she said she felt was “one of the great love stories on ‘Grey’s Anatomy.’ ” “I don’t have story lines that I feel are unsuccessful, or else we wouldn’t have put them on television,” she said.

“I can listen to everyone’s shouts of ‘Izzie’s having ghost sex!’ and laugh a little bit,” she continued, “because I know where it’s going.”

If, as has long been rumored, where it’s going includes Izzie’s death and Heigl’s departure from the show at the end of the season, Rhimes isn’t sharing. With anybody. Save for one person.

Rhimes said she has laid out the specific details of the story line, which recently included the revelation that Izzie’s seriously ill, with only Stephen McPherson, president of ABC Entertainment.

During the network’s portion of the Television Critics Assn.’s press tour last month, McPherson allowed that the story “might not be [everyone’s] cup of tea.” But Patmore-Gibbs, who has an idea of its “general direction,” as she put it, stressed that the network remains firmly behind Rhimes. “We believe in where we’re headed,” she said. “We have an enormous amount of trust in Shonda as a show runner.” In fact, in late January, ABC greenlighted a new drama pilot, executive-produced by Rhimes, called “Inside the Box.”

Of course, at this point, “Grey’s” has made nearly as many headlines for its behind-the-scenes intrigue as its on-screen plot twists.

Two years after the Isaiah Washington drama, Rhimes and the network faced charges of homophobia after the abrupt firing of Brooke Smith, who played Dr. Erica Hahn and, together with Ramirez, made up “Grey’s” first significant same-sex couple. More recently came reports that T.R. Knight, unhappy with his character George’s lack of screen time this season, had asked to leave. .

All of which makes a visit to “Grey’s” Prospect Studios stages a unique experience. On this mid-January day, two publicists -- one from the network, the other from ABC Studios -- hovered closely, occasionally offering up unsolicited assurances about the set’s harmony quotient. Perhaps they felt the need to fill the silence left by several of the show’s stars. Dempsey, Pompeo and Ramirez all declined to sit for interviews, and neither Heigl nor Knight was on set that day.

“I didn’t know if I was gonna talk!” said Sandra Oh with a loud laugh. “You caught me on a good day.”

The negative media attention has made the cast “wary,” she explained. “Quite honestly, I don’t think people are really interested in the effects that it has on the people who are being scrutinized,” Oh said. “It’s very difficult to keep a handle on it.”

Dane echoed the sentiment. “I’ve adopted the attitude ‘enough already,’ ” he said, noting that, on set, “People have their moments, and let’s just try to understand them for what they are.”

Oh said her experience on “Grey’s,” where she plays competitive resident Cristina, had taught her that “work as a television actor is not just acting, at all.” How so? “At this point, these are long-term work relationships that consistently have to be nurtured.”

That includes relationships with those that provide the material. “The times that I’ve had conversations with the writers about my concerns,” said Oh, “sometimes it’s responded to and sometimes it’s not. That’s just the way it goes.”

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Actor-writer relationships

On set, Dempsey found his concerns responded to, though maybe not in the way he would’ve liked.

“See that face?” he said, nodding in the direction of Tony Phelan, the writer/co-executive producer on set, who didn’t look particularly thrilled at the suggestion of more screen time for Derek and Meredith. “That’s what I deal with.”

“I’ll trade jobs with you,” Phelan retorted. “Why don’t you come into the writers room and try to write for all 29 of you?”

Dempsey laughed. “They wouldn’t wanna see me write,” he said. “We’re trying to keep the show on the air.”

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