Adam Sandler is playing his career game exactly right. After establishing himself as a juvenile fool in a string of low-box-office, high-renting films, Sandler went legit with 1998’s The Wedding Singer. That funny, romantic screwball comedy skewed his audience older and slightly more sophisticated than the frat-house crowds who were Happy Gilmore’s repeat renters. The Waterboy marked a return to form, establishing good will toward the core Sandlerites and also raising his profile—now he was the guy from The Wedding Singer, a real movie, and mainstreamers paid attention. Big Daddy is the next logical step in Sandler’s maturation process; for this film, Sandler’s character is saddled with a son, next to whom he can’t help but look marginally more mature. He hasn’t alienated his huge male following—he’s still gleefully crude, childish, and given to fierce rages. But as a lovable loser with a tousle-haired tot…Can you say, “Chick magnet”?

Sonny Koufax rooms with his more determinedly successful pal Kevin (Jon Stewart) in a bachelor’s playland of a loft, sleeps late, watches cartoons over a bowl (or handful) of Cap’n Crunch, and works one day a week at a tollbooth just to keep his hand in. Sonny can’t bear maturity in others, the way drinkers get defensive around teetotalers; he’s addicted to the liberating minor anarchies of childishness. He clings to friendship with Kevin, even though Kevin already has one mental foot out of the loft festooned with canned food and beer signs, and won’t let Kevin’s brittle blond fiancee, Corinne (Leslie Mann), now a doctor, forget that they met her as a Hooters girl. Reminding her of her tiny-T-shirt past is somehow comforting to him—that was before any of his circle had their lives sorted out to their satisfaction—and has the added benefit of pissing Corinne off. Now Sonny’s old gang has grown up and paired off (even attorneys Tommy and Phil; the former fratmates have paired off with each other) and his lone jerky-boy act is wearing thin. Frustrated with his laziness, his girlfriend dumps him for a much older man.

Big Daddy’s home-run premise is designed to raise Sandler’s profile in the world of grown-up film; while Kevin’s away on business, Social Services drops off a perfectly adorable 5-year-old at the loft door announcing that the kid is Kevin’s from a previous liaison. On a whim, Sonny decides to let the kid hang around until the situation can be sorted out. Before you can say, “Awwww,” Sonny’s bonding with little Julian (played by twins Cole and Dylan Sprouse) the only way he knows how—by being a better 5-year-old than an actual 5-year-old can be.

The scenes of Sonny rewriting the rules of parenting with Sandleresque caprice have an infantile, roguish charm, much like Sandler himself when he moves his comedy beyond one-note themes like the pitiful bullyboy wish-fulfillment of The Waterboy. Sonny schools Julian with weapons from his own arsenal of juvenilia—the stick in the Rollerblader’s path, the hawk-and-suck, the vengeful wall-piss. He’ll do anything to cheer up the kid, including getting himself hit by a car. But it’s not all bratty fun and games. Big Daddy imbues Sandler’s character with a higher baseline of maturity from the start than he usually gets, so Sonny’s eccentric behavior is not indelible or even particularly damaging for Julian. When Julian wants more from Sonny than just junk food and buddy antics, Sonny responds, bewildered at first, but with increasing confidence, proving that his own childishness and indolence are just affectations.

The script is too smart to sacrifice consistency for gags, so when Sonny tells Julian he can wear what he likes, every day is Halloween, for the rest of the film—although on Halloween proper, Julian’s little mad-lobster costume isn’t as cute as the mini kimono or the plaid cummerbund and yellow waders. The old Sandler might have been paired with a kid as a sort of superdestructive sidekick, acting out in ways that might be unforgivable for even Sandler’s characters, but Big Daddy’s father-son fantasy strives, in its own way, for realism. Sonny’s experience with Julian comes just as he is ready to resolve his relationship with his own gruff, judgmental father; while dealing with a kid, Sonny can’t help puzzling over the father-son thing—he hectors a goth in Central Park as an example to Julian of how dads mess up their boys. “Let it go!” he yells at the annoyed man in black. “He can’t hurt you anymore!”

When Julian takes his wacky outfits and wild manners to school, Sonny discovers with a jolt that he has been breeding a sociopath with lamentable hygiene. But he cleans up the kid, and his own life, with help from pretty Sierra Club lawyer Layla (Joey Lauren Adams); soon a weird postnuclear almost-family is created out of thin air, good will, a little research, and some Pop-Tarts. Sonny’s horror at how the crude anarchism he has taught Julian plays in the kindergarten big time is emblematic of Big Daddy’s point and raison d’etre—even Adam Sandler is growing weary of jeering, junk-food Adam Sandler humor.

The story follows a well-trodden path, but it does take some interesting side trips; neither Sonny’s situation nor its resolution is effected as easily as it could have been by a lazier script. Just when it looks as if Sonny will lose Julian to the state, all the lawyers in his life, including Dad, show up for a courtroom scene that is as unusual in its restraint as it is unlikely. No one gives a moving speech about what a tender-hearted dad Sonny makes; his own father doesn’t break down and admit he loves his kid; in fact, Sonny’s character witnesses—a homeless guy (Steve Buscemi) to whom he slips McDonald’s, the deli deliveryman (Rob Schneider) who practically lives at the loft, the spiteful Corinne—are a sorry lineup. The film’s resolution is a bittersweet compromise that, amazingly, puts the kid’s needs before the star’s. Big Daddy makes raising a child look like so much fun, you want to run right out and snatch one. CP