When buzz is waning and ratings are down, TV execs often initiate the Heather Locklear Maneuver add one bitchy blonde, and then watch the watercooler talk bubble. MTV is the latest to put its faith in this move: EW can confirm exclusively that former Laguna Beach bad girl Kristin Cavallari will be replacing Beach alum (and onetime frenemy) Lauren Conrad as star of The Hills. Producers hope that Cavallari the memorably catty player in Beach's Kristin/Stephen/Lauren love triangle will reinvigorate a show that's struggled recently to find compelling story lines (Heidi and Spencer in couples counseling? Really?) and is down 14 percent in viewership versus last season, with 2.5 million. And Cavallari, who will appear in the May 31 finale and 10 episodes in the fall, is fully prepared to shake up The Hills. ''It's a TV show,'' she says bluntly. ''I'm not going into it like, 'I'm going to make great friendships with these people.' It's work! And drama sells. I think that's why they're bringing me in, because I know what works.''
When Conrad announced in February that she was fleeing The Hills to lead a camera-free life, producers Liz Gateley and Adam DiVello weren't sure how much longer the show could go on. ''We all took a hard look at whether it was worth continuing,'' says Gateley, who is also an MTV development exec. But the pair had never forgotten about Cavallari, 22, a breakout star from their previous series, Laguna Beach. ''We spoke to Kristin a few times about [The Hills],'' says DiVello, but ''there was never a natural time to bring her in.'' That is, until they found themselves without a leading lady. ''With us wanting to put a new spin on the show,'' explains DiVello, ''she was a natural choice.'' Cavallari, an aspiring actress whose post-Laguna career has included hosting UPN's 2006 reality series Get This Party Started, was initially hesitant to return to her reality roots. ''It's taken me a while to get rid of the 'reality star' label, and this is just going to put it right back on,'' she says. Still, the risk of typecasting was outweighed by the promise of a potentially lucrative boost in her Hollywood visibility. ''The goal is to get people excited about me again,'' says Cavallari, who has two comedies, Van Wilder: Freshman Year and Wild Cherry, set for release this summer. ''When I first started out I had a celebrity name, but I didn't have the acting skills I have now. So if I have some buzz again, it will only help.''
Cavallari will be reintroduced into L.A. reality society during Heidi Montag and Spencer Pratt's season-finale wedding (she catches the bouquet, naturally). Sure, the producers asked Montag and Pratt to add the show's new star to their guest list but it's not completely random that she was there: Cavallari says she and Hills costar Brody Jenner set up the newlyweds in 2005, making her Patient Zero in the Speidi epidemic. Cavallari's story line will really take off in the fall, when her dating life will provide much fodder: ''I'm very open to dating and going out with my girlfriends and just having a good time.'' While The Hills has always been subject to scrutiny over its authenticity, producers deny recent rumors that they are plotting a romance between Cavallari and laconic Hills hunk Justin ''Bobby'' Brescia. Says Gateley, ''I'm sure Kristin will give us plenty of plotting of her own. We do not need to plot for her.''
Still in question is how much of her life as a struggling actress like all those auditions and drama classes will make it into the show. (Producers have routinely avoided including any aspect of Conrad's real celebrity in the series.) ''With The Hills, they try and only show the glamorous life we live out here,'' says Cavallari. ''They don't want to show me going to auditions and not booking a job. That's just not glamorous.'' Adds Gateley, ''We'll have to see along the way how much that comes out in her day-to-day dialogue with her friends. We'll edit it accordingly as we do with everyone.''
While The Hills may be a new show for Cavallari, it's filled with friends or, at least, girls she's chatted with on line for the bathroom at Crown Bar. ''I actually do know everyone,'' she says. ''I went to high school with Lo [Bosworth]. I've hung out with Audrina [Patridge] a few times. Stephanie Pratt was the only one I didn't know who I just met at the wedding.'' As for her onetime nemesis, Conrad, the two are now cordial. ''A few months ago, I ran into her and a couple other friends from high school and we hung out all night,'' she says. ''I think we both just kind of grew up.'' Since MTV is expecting Cavallari to deliver boozy hookups, boyfriend theft, and quotable bitchery, here's hoping she hasn't grown up too much.