Timothy Hutton, Sean Penn, Matt Dillon, Rob Lowe, Matthew Broderick—it seems there are enough young leading men in Hollywood these days to form a baseball league. And right at the top of the starting lineup would be Tom Cruise, 21, star of the surprise summer hit Risky Business. "He occupies this movie the way Dustin Hoffman occupied The Graduate," raved critic Roger Ebert. Playing a straight-arrow upper-middle-class kid who loses his virginity to a call girl and then provides his friends with the same service—for a profit—Cruise radiates a sexy all-American charm. "Tom is able to bridge innocence and heat," says his director, Paul Brickman. "It's a difficult range, but he's got it naturally."

That's high praise for someone who never really thought of acting until his senior year in high school in Glen Ridge, N.J. When a wrestling injury sidelined his athletic pursuits, Tom tried out for a school production of Guys and Dolls. "It just felt right," he recalls. "It felt like I had a way to express myself." Since he "didn't have any inspiration" for college after graduation, Cruise went to New York, and within months he had his first film audition for a small role in Endless Love. Director Franco Zeffirelli gushed, "Bellissimo," and signed Cruise for his first movie.

From then on it's been three years of nonstop work: as the psychotic Red Beret leader in Taps, as a greaser in The Outsiders, and as a high school football player in the not-yet-released All the Right Moves. "I work very hard," Cruise says. "My craft is the most important thing in my life." For each new character, Tom not only focuses on accent and motivation, but like Robert De Niro, he also resculpts his body. For Taps, he gained 15 pounds by swigging milk shakes. For The Outsiders, he had the cap removed from a front tooth that had been chipped by a flying puck in a hockey match, and to the distress of some of his colleagues he refused to shower during most of the nine weeks of shooting. For Risky Business he shed 14 pounds in five weeks by jogging in the Florida sun and strict dieting. When he had reached his weight goal, he stopped exercising "so I could put on a little layer of baby fat" for his unathletic character. "He's a very vulnerable person," Tom explains. "I didn't want any physical defenses up for him. No muscle armor at all."

Athletics served as Tom's armor when he was growing up. His father's job as an electrical engineer required the family to move constantly. The discomfort of being the new kid on the block was aggravated by dyslexia, a learning disability that Tom shares with his mother and three sisters. "I was put in remedial reading classes," he says. "When you're a new kid, all you want to do is blend in with everything and make friends. It was a drag. It separated you and singled you out." He made himself popular by excelling at virtually every sport—wrestling, hockey, lacrosse, tennis, football, baseball and skiing. "I would pick up a new sport as a way to make friends," he explains. "I'd go up and say, 'Do you play tennis? Do you want to play sometime?' "

When Tom was 11, his parents were divorced, and he and his sisters went to live in Kentucky with his mother, who teaches dyslexic and hyperkinetic children. (Five years later she was remarried to a plastics salesman.) "Everything was chaotic," Tom recalls. Looking for a "structured environment," he enrolled in a Franciscan school for a year, and even thought briefly of becoming a priest.

Now he finds that acting satisfies his need for self-expression. He's been lucky in finding directors who incorporate his suggestions into his movies. In Taps, at his urging, a scene was added that showed his gung-ho character pumping iron. In Risky Business, right after his parents leave him alone in their large suburban house, Tom celebrates his new freedom by mugging as a rock star in his underwear. Improvising the scene—one of the film's highlights—was his idea. "With kids," he explains, "to be a rock star is the ultimate. When their parents leave, they turn the music up. Dancing with your pants off—it's total freedom."

Tom's career has cut into his own freedom. With little time for social life, Tom has no girlfriend and lives in apartments rented wherever he happens to be working. "Everything I have fits into two suitcases," he says. The landlady of his current two-bedroom rental in Brentwood finds it a "treat to have such a nice quiet boy around. There's never any loud music up there." Tom likes to hang out with his friends—actor Emilio Estevez (Martin Sheen's son) is a close buddy—and he enjoys cooking, especially pasta and fish. But most of the fun comes from his work. "I enjoy the pressure of making a movie," he says. "It's like getting psyched up for a wrestling match—but with higher stakes. I thrive on it."