THE NEW 'DESPERATE' HOUSEWIFE PASSED ON WISTERIA LANE ONCE BEFORE

[Brian Damage]

October 7, 2007 -- When Dana Delany joined the cast of "Desperate Housewives" this season, she naturally expected her character - insta-neighbor Katharine Mayfair, wife to a handsome gynecologist and mother to a gorgeous teenage girl - to be the show's newest wacky homemaker.

Then she realized all of Katherine's scenes with the other ladies on the block were taking a decidedly prickly tone. "I was just being kind of bitchy to everyone," says the New York-born actress, "so I finally said to Marc [Cherry, the show's creator/executive producer], 'What am I, the Antagonator?'

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"So that's what I've named myself: The Antagonator. I've coined a new word!"

Delany's poised and persnickety Katharine may be new to fans, but in the world of the show she's a returning figure, having lived on Wisteria Lane 12 years prior, and leaving originally under - what else? - mysterious circumstances.

In a way, Katharine's Wisteria bonafides are a nod to the fact that Delany has her own "Housewives" backstory. She was Cherry's first choice to play the image-obsessed martinet Bree.

Curled up on a chair in a hotel suite in Los Angeles, Delany explains turning Bree down.

"I had done 'Pasadena' [Fox's short-lived rich-family nighttime soap from 2001] and it just felt like too familiar territory," she says. "I tend to be reactive. And then it turned out to be a huge hit."

Delany, who has two Emmys for her breakthrough role as nurse Colleen McMurphy on the critically lauded series "China Beach," easily stayed busy with new roles - she lives to work, she says - but her last attempt at a regular series, NBC's "Kidnapped," was quickly axed.

Cherry's second offer over the summer is rare in Hollywood, she says.

"I've said no to other people and they never want to work with you again," she says. "So I admire Marc for coming back. Marcia [Cross] has totally made Bree her own character, and now Katharine is right for me."

As for whether her well-established sex appeal will spice things up on the show, the 51-year-old Delany – whose cheery, un-surgerized Irish beauty is still magnetic – says so far Katharine's secret-keeping has dominated.