It’s true that a 90210 reprise without Brenda was unthinkable for longtime enthusiasts. “If you have a show called 90210 and you’re bringing characters back, you can’t not bring Shannen Doherty back,” says Kevin Smith, a noted Dohertyolgist since their Mallrats days. “That’s like putting on Hamlet and leaving out Hamlet.”

But Doherty has returned for another reason: She’s looking to rewrite the personal history of her alter ego, and maybe her own. Doherty wouldn’t commit to 90210 until she was given assurances that Brenda wouldn’t wear an arrested pout. Ms. Walsh implausibly returns to West Beverly High from Broadway, as a drama teacher.

“I wouldn’t have done it if she was stuck in the same spot,” Doherty says. “There were moments when I hated Brenda, but there were other moments when I saw vulnerability and greatness in her, and believed her passion for life would make her a great actor—but not someone you would necessarily want to hang out with.”

Doherty’s view of her own past is Rumsfeldian “stuff happens” with a sprinkle of “life’s a journey” pixie dust. “I wouldn’t be the person I am now if I had not had those experiences,” Doherty says. “Do I say ‘Ooh, I wish I hadn’t done that?’ Sure. But I don’t regret anything, because I think I’ve turned out to be a pretty good person.”

Doherty was born in Memphis to Tom and Rosa Doherty, devout Southern Baptists who’ve now been married for 40 years. (The family relocated to Southern California when Shannen was 7.) “Try dating when you have ridiculous expectations,” Doherty says. “My father is a gentleman. When you’re used to that, it’s a culture shock.”

Confronted with the observation that none of her paramours have been exactly genteel, she lets out a giant laugh. “Um, I think I’ve admitted I haven’t made the best choices in men,” she says.

Perhaps her biggest personal blunder was marrying Rick Salomon in Las Vegas in 2002. The marriage was later annulled, but it still made Doherty the answer to an unwanted trivia question: Who was Rick Salomon involved with before he made the Paris Hilton sex tape?

Nevertheless, Doherty is sticking to her “no regrets” line. “There was something that Rick provided that was amazing to me,” the currently single actress says. “I look at what he did [with Hilton] and think, God, that’s disgusting. But when we were married, I never had someone make me laugh so much. I was madly in love. It was a really hard marriage. When it ended, it was a heart-crushing thing.”

Doherty is slated to appear in just a handful of 90210 episodes. “We all agreed we’d see how it goes,” she says. Her first day on set was marked by knocks on her trailer door as the new kids shyly paid their respects to the veteran. “They’re so much better prepared for this than we were,” Doherty says. “We were on a new network and had no idea what was about to happen. It just happened so quickly.”