The filmmaking team behind ''Shrek'' takes the bare bones of William Stieg's children's book about an ogre who thinks filthiness is next to godliness and glories in bad manners and ickiness and uses that as a taking-off point for a new animated film that rejoices in its own brand of perversity.

The opening sequence of the film -- a Dreamworks movie directed by Andrew Adamson and Vicky Jenson and written by Ted Elliott, Terry Rossio, Joe Stillman and John Powell -- features the title monster (voiced by Mike Myers) enjoying a mud bath. It isn't merely because it will keep his glowing green skin supple and youthful; like the picture's young target audience, who love to display mouthfuls of half-chewed food to giggly friends and outraged adults, he loves creepy slop. (He garnishes his martinis with a human eye instead of an olive.) The movie itself is a giggly cocktail, though it's more foam than drink, a return to the frothy riffing on pop culture that started back on Bugs Bunny's watch in the Vitaphone days, before Disney created the fairy tales that were 90 percent merchandising and 10 percent boredom. ''Shrek'' maintains that beauty is on the inside, not the outside.

Mr. Myers subtly nudges his fans by giving Shrek a gentler version of the Scottish burr he employed for the least likable characters in ''Austin Powers: The Spy Who Shagged Me'' and ''So I Married an Ax Murderer.'' Eddie Murphy is also one of the voices in ''Shrek,'' playing a needy donkey who has been promoted from supporting character in the book to sidekick. It gives Mr. Murphy a chance to reprise his desperate-to-ingratiate character from ''Mulan,'' probably the subtlest of the film's many relentless jabs at the bland ubiquity of Disney's animated characters.

Shrek is just as desperate as the donkey, but it's because he wants to be alone. Lord Farquaad (John Lithgow) gives him the opportunity to return to his jolly, green hermetic state. If Shrek can deliver Princess Fiona (Cameron Diaz) for Farquaad to marry, Farquaad will ensure that Shrek's swamp is restored to its isolated status. The ogre sets off on his adventure with the donkey scampering behind, keen to help. Farquaad is responsible for Shrek's plight. He has assigned all of the magical creatures of the kingdom to ''a designated resettlement facility'' and many of them -- the Three Little Pigs, Pinocchio and others -- are on the run. They're using Shrek's mossy home as a hideout, which makes his mission all the more urgent.

Much of ''Shrek'' is scrappy, brash comedy, and the brio of the actors adds to the dynamism. The cycle of kiddie musicals typified by ''Aladdin'' seems to be drawing to a close, possibly because video stores have walls of these animated sing-along films already. Nonetheless, in a bleak nod to that tradition Shrek himself has been saddled with a bit of pathos: he's only vile because he wants to pre-empt responses to his appearance. Fortunately, he doesn't break into song to explain his aching psyche, though he might as well.

In Mr. Steig's book, Shrek is unapologetic about his looks; for him, life is not trick or treat, it's trick and treat.

Like many movies nowadays, ''Shrek'' is a blistering race through pop culture, and what the movie represents is a way to bring the brash slob comedy of ''The Simpsons'' and ''South Park,'' as well as the institutional irreverence of ''Saturday Night Live,'' to a very young audience. This leads to some very funny scenes, like the torture of the Gingerbread Man. Such rambunctious heartlessness has become a way of life in children's animation, but television isn't equipped to do it as well as films can.

When ''Shrek'' is cooking, thanks to the writing as well the improvisational skills of stars like Mr. Myers and Mr. Murphy and the performance of Mr. Lithgow, the jokes have a bark. The film's co-producer, Jeffrey Katzenberg of DreamWorks, is taking cartoons back to their roots. They weren't originally created for children but were consigned to the early morning children's ghetto in the early days of television because they were colorful, imaginative and short.

Beating up on the irritatingly dainty Disney trademarks is nothing new; it's just that it has rarely been done with the demolition-derby zest of ''Shrek.''

''Shrek'' is rated PG (''Parental guidance suggested'') for some slightly adult references that parents may have to find a way to explain.

SHREK

Directed by Andrew Adamson and Vicky Jenson; written by Ted Elliott, Terry Rossio, Joe Stillman and Roger S. H. Schulman, based on the book by William Steig; edited by Sim Evan-Jones; music by Harry Gregson-Williams and John Powell; production designer, James Hegedus; produced by Aron Warner, John H. Williams and Jeffrey Katzenberg; released by DreamWorks Pictures. Running time: 89 minutes. This film is rated PG.

WITH THE VOICES OF: Mike Myers (Shrek), Eddie Murphy (Donkey), Cameron Diaz (Princess Fiona), John Lithgow (Lord Farquaad) and Vincent Cassel (Monsieur Hood).