Eight years after ditching his Fresh Prince moniker, Smith, 35, has grown older but hasn't completely grown up. The conflicted cop he plays in the sci-fi thriller "is the complete opposite of Will Smith," he says. "This is a dude that walks about every day unhappy. And that is not me at all. I am tickled pink." Why wouldn't he be? With a still-sizzling film career (hit sequels to Men in Black and Bad Boys) and a six-year marriage to Jada Pinkett Smith, 32, "he really enjoys his life and works very hard because he likes what he does," says I, Robot director Alex Proyas. "That rubs off on the entire crew."
Even when the cameras are off, Smith provides plenty of entertainment value for his $20 million-plus-per-film paydays. He bellowed intentionally off-key renditions of'70s and '80s love songs to entertain I, Robot's cast and crew during tedious late-night shoots. "There is nothing better than showing up to work, and Will is there, and things are out of control;' says costar Shia LaBeouf. Yet there is a method to his madness. "People are my energy," he says. "I can't function if somebody is uncomfortable." Only costar Bridget Moynahan was spared from Smith's practical jokes. "I think Jada told him not to pick on the lead actress," she says. "That's a house rule."
And what Jada says, goes. "Just like in my house when I was growing up, I knew that my mother was the center," says the Philadelphia native. "If Mommy is straight, then everybody else will be. I am very clear at home that Jada's physical, mental, spiritual health and comfort comes first." The result is "an incredible family structure," says Moynahan of the clan, which includes son Jaden, 6, daughter Willow, 3, and Smith's son Trey, 11, from his first marriage. "He is definitely a good role model."
One who immediately squelches any rumors of relationship rifts. "There is not now, never has been, and there never will be any trouble in paradise," Smith told PEOPLE in April, after rumors suggested an imminent split. Smith traveled to London later that month to cheer on Jada and her rock-soul band, Wicked Wisdom, who opened for Britney Spears's U.K. tour leg. "I step up when she needs me to step up," Smith said, "and back up when she's got it."
Smith also hasn't forgotten about his own music career ("Acting just pays the bills a little better," he says). He spent I, Robot downtime recording in his trailer and plans to release his next album by Christmas. Onscreen he's laying down his weapons for next year's romantic comedy The Last First Kiss and October's computer-animated Shark Tale (he voices a fish), but promises to return to his blockbuster shoot-'em-ups before long. "I feel like I have got five or six more years of action movies," he says. "I want to hurry up and get those, while I can still take my shirt off in a movie."
Jason Lynch. Sean Daly and Margi Blash in Los Angeles