The average musical would be a helluva lot better if its heroine, when belting out a saccharine tune, got hit in the face with a dodgeball. That’s what happens when Tracy Turnblad sings the puppy-love ode “I Can Hear the Bells” in Adam Shankman’s tremendously entertaining Hairspray, a remake of John Waters’ 1988 original via its 2002 reincarnation on Broadway. And she doesn’t miss a note.

Tracy is a zaftig teen in 1962 Baltimore who wants nothing more than to strut her generous amounts of stuff on the hot local dancing program, The Corny Collins Show. Every day, Tracy (Nikki Blonsky) and her dopey friend, Penny (Amanda Bynes), run home from school to shriek at the TV as the area’s most popular kids, including Amber von Tussle (Brittany Snow), do the Mashed Potato with pasted grins in front of the camera. When one of the dancers drops out—“Only nine months,” she responds when Corny (James Marsden) asks how long she’ll be gone—Tracy knows it’s her chance to get in the spotlight. Her equally oversize mother, Edna (John Travolta), fears she’ll be turned down because of her weight, but her father (Christopher Walken) tells Tracy to go for it.

That’s right: Mom and Dad are John Travolta and Christopher Walken. Together at last! As freakish as Mr. Saturday Night Fever looks in a fat suit and makeup as he reprises the role originated by late drag queen Divine, you may be surprised to find yourself warm to his version of a sweet, shy housewife opposite Walken’s adoring—if, as always, a bit creepy—husband. Of course, this being a musical, the cast members weren’t chosen only for their acting chops, and Travolta steals several scenes as Edna is coaxed by her daughter to bust a move—not heels nor fake flab keep the actor from quite skillfully shaking his ass. Some of the movie’s best moments, though, develop when the couple are together. Imagine Walken comforting his weepy, gigantic male wife. Or the two doing a little soft-shoe in the moonlight.

The pair are representative of Shankman’s biggest achievement: making a film that manages to be slightly subversive, very goofy, and relentlessly feel-good at the same time. Tracy is a potentially insulin-raising bubble of optimism and cheeriness, believing that she can do anything despite not being skinny and blond—and she proves it, by becoming one of the most popular dancers on Corny’s show. But she’s forward-thinking, too. When she gets punished in school for “inappropriate hair height,” Tracy meets a group of black students, including Seaweed (Elijah Kelley) and his little sister, Inez (Taylor Parks), who use their detention time to dance. The kids aren’t allowed to appear with the white teens on the program and are instead restricted to a once-monthly “Negro Day.” When Negro Day is canceled altogether, though, thanks to the TV station’s manager (Michelle Pfeiffer)—who also happens to be Amber’s competitive mother—Tracy protests, marching with her black friends to try to force the station to integrate.

Shankman and his writers—Waters, Leslie Dixon, and the stage musical’s Mark O’Donnell get credit for the screenplay, with Scott Wittman responsible for lyrics—are able to smoothly incorporate such a serious theme exactly because the rest of the movie refuses to take itself seriously. Every treacly sounding, showstopping song (and the film’s full of them) hides jokes and political incorrectness among its earnest lyrics. (Penny, who falls in love with Seaweed, sings: “In my ivory tower/Life was just a Hostess snack/But now I’ve tasted chocolate/And I’m never going back!”) One-liners pepper the script too, always zinging just in time to erase whatever goopiness has been building up.

Travolta and Walken aren’t the only cast members who are terrific. Blonsky, looking like she could be the daughter of the original film’s Ricki Lake, is infectiously sweet and great with a tune. But the smaller players are gems as well, particularly the usually blank Bynes, who subtly brings out the innocent Penny’s sexiness, and Marsden, who looks more alive as a song-and-dance man than he has in any of his mouth-breathing dramatic turns. And as is the case with many remakes, the cameos offer a giggle, too. Perhaps the biggest surprise of all, though, is Shankman, whose previous directorial efforts—the terrible Cheaper by the Dozen 2 and The Pacifier—didn’t exactly make him an obvious choice to steer a summer musical. Turned out that he and crew needed only a little Hairspray to make something unforgettable.