It was supposed to be just a joke. Or at best, an elaborate, high-concept journalistic experiment. In November 1996, aspiring actress Ali Larter appeared on the cover of Esquire as ”Hollywood’s Next Dream Girl.” The catch: Larter was actually playing a woman named Allegra Coleman, a fictional character concocted by the magazine’s editors. (The photos showing Larter/Coleman at parties with Quentin Tarantino and on the arm of ex-boyfriend David Schwimmer were fakes.) But a funny thing happened to Larter’s 15 minutes of fame: That celebrity-profile parody actually helped make her almost as hot a Hollywood property as her alter ego. This season she’s had a recurring role on Dawson’s Creek as Pacey’s lust interest. In January she’ll make her feature debut opposite Dawson himself, James Van Der Beek, in the gridiron drama Varsity Blues. And the actress has just completed her second film, Next to You, costarring Melissa Joan Hart. What does Larter make of the ironic turn of events? ”When the door opens for you in Hollywood,” she says, ”you need to run with it. You know?” We know.