BEVERLY HILLS, Calif. -- It’s a typically twisted showbiz irony: When the cast and creators from one of the most-anticipated new fall shows came to face the press, Topic A was the one person who wasn’t in the room.

Still, producers of the CW network’s new 90210 couldn’t wait to drop their big news Saturday to a roomful of TV critics: Shannen Doherty, the buzzed-about, troubled former star of Beverly Hills 90210, has agreed to join the cast of their 21st century reboot.

Doherty joins original 90210 alums Tori Spelling and Jennie Garth in the new show, playing a grown-up Brenda Walsh as a successful theater actress who returns to her old alma mater to direct a musical production.

But 90210 star Lori Loughlin, who was toiling away in the cast of the classic sitcom Full House when the first edition of 90210 was redefining television, urged critics to keep in mind that returning stars such as Doherty, Spelling and Garth won’t be the core of the revamped series. 

“It will be a new show…we certainly don’t want people tuning in, thinking they’re going to see Luke Perry and Jason Priestly and Brain Austin Green, because they’re not,” said Loughlin, who plays the mother in a couple moving their kids to Beverly Hills from Kansas to care for her mother-in-law, a faded TV star-turned-alcoholic.

“It is a new group of kids at West Beverly High, with new teenagers and new issues,” she said. “Kids are exposed to a little bit more at an earlier age. Stuff that we were dealing with in college, maybe they’re dealing with in high school. They want to show this new world of teenagers today.”

Critics here noted that the first 90210 was a groundbreaking show, which centered on a glamorous collection of teenage characters at a time when few show paid attention to that age group. The new edition hopes to draw in both fans of the old show and curious youngsters, featuring classic characters grown up and a re-imagining the show’s old diner hangout, The Peach Pit, as a cool coffeehouse with an upstairs club.

Critics also noted this is the series which could save the flagging CW: a buzzed-about production which might actually draw a wide spectrum of viewers. “It’s huge pressure…but you just have to do your job," said executive producer Gabe Sachs. "The network and the studio, they’re concerned about every little part of this, because this is a big deal to them. Gone are the days when a network says 'Hey creative people -- here's a pile of money, go make your TV show.'

Sachs and his partner Jeff Judah hope to bring the same subversive spirit which made past shows they’ve written – Freaks and Geeks, Undeclared and Just Shoot Me – critical favorites. They also hoped to retain their reputation for keeping a tension-free workspace, despite the addition of Doherty, who left the first 90210 and her later series Charmed, amid rumors of sharp disagreements with producers and co-workers on both shows.

Speaking to reports after the session today, Sachs downplayed any notions of Doherty as a trouble maker -- though her offscreen antics years ago were legendary, from getting arrested for assault in the '90s to a DUI charge in 2001. He said someone from her camp called him as news of the reboot was circulating Hollywood, and they eventually agreed to meet at a restaurant to feel each other out.

“I couldn’t judge her, I’d just heard these stories about her…but we brainstormed on ideas and she was so excited,” said Sachs of Doherty. “We’re including her, and I think maybe her (previous) experience was very different.”