Age 25 Why her? It's no secret that this former model is a seriously pretty face. But the problem with most models-turned-movie stars is that they end up playing part of the scenery. And for a time that was true of Diaz, too: Her roles in 1996's Feeling Minnesota and She's the One didn't leave much of an impression, but then came her turn in My Best Friend's Wedding. The movie was heralded as Julia Roberts' comeback, but it also marked Diaz's coming of age. Her hilariously humiliating karaoke scene revealed: (1) her voice was not as pretty as her face, and (2) this was one blond who had more funny than anyone had previously suspected. Now, in the Farrelly brothers' There's Something About Mary, out July 15, she gets her first chance to really throw down. Diaz bravely endures what may be the sickest, most sidesplitting sight gag since John Waters went mainstream. Another role likely to add to her comic luster is in Very Bad Things, about a bachelor party gone bad, out this fall. What made actor-director Peter Berg choose Diaz over her peers? "A unique combination of beauty, fearlessness, and a banging sense of humor," he says. Adds Bobby Farrelly: "Cameron's like Grace Kelly—but with gas." Laughing, of course. Work habits "A handbag full of tricks. I use music to bring emotion to the surface." She also likes to watch. To make Mary's high school scenes convincing, she went back to her alma mater, California's Long Beach Polytechnic High School, and spied. "Younger girls aren't comfortable with their bodies yet. I learned a lot about walking from them." Whom she'd like to work with Harrison Ford. On a recently taped Rosie, O'Donnell presented Diaz with an autographed picture of him. "Dear Cameron," it said, "I'm still available." Diaz pretty much swooned. "He's my poster boy for masculinity." Next? Oliver Stone's Any Given Sunday.