To get the title out of the way first, "O Brother, Where Art Thou?" is the name of the 'important' movie that film director Joel McCrea, who's made nothing but fluffy movies, wants to make in Preston Sturges' 1941 film "Sullivan's Travels." So he leaves Hollywood with a dime in his pocket to see for himself the 'real' America, in the course of which he finds himself robbed, beaten, falsely arrested and imprisoned, and then, in jail, gets to see one of his own escapist films projected for the prisoners.

Does that help? Not really, because Joel and Ethan Coen haven't made that movie. Nor have they made what they call their version of the Odyssey, even though they've populated the film with a lead character named Ulysses, a seer, three sirens, a cyclops, a wife-left-behind named Penny, as in Penelope, and probably a lot more that I didn't spot.

In "O Brother," which is set in a Mississippi of the 1930s, three escapees from a chain gang -- George Clooney (as Ulysses Everett McGill), John Turturro as Pete and Tim Blake Nelson as Delmar -- wander through the delta country looking, more or less, for a supposed hidden treasure. Clooney, the bright one, is their leader, in a performance that's a lovely homage to Clark Gable, bright eyes, trim mustache, barking voice and all. During their odyssey they encounter all of the above, plus Baby Face Nelson. They're captured, escape, are recaptured, re-escape, and no one seems too put out by it all. The film is about their odyssey and pays no more attention to reality than it needs to, which is not often.

Music is threaded throughout, mostly old Appalachian gospel and folk songs, from 'Big Rock Candy Mountain' to 'Man of Constant Sorrow,' which in one episode they record in a beautiful version at a country music station for ten dollars, calling themselves the Soggy Mountain Boys, though we've never heard them sing before. It's that kind of movie. The sirens sing them a gorgeous sexy ballad, which bewitches Pete right out of his clothes, and perhaps changes him into a toad.

The boys -- we can use the 1930s terminology -- also find themselves in the middle of a political campaign that features Pappy McDaniel (Charles Durning) as the incumbent governor and his no-brain trust; and they rescue their young black guitarist from a lynching by the Ku Klux Klan -- hundreds of them in white sheets and hoods marching and pirouetting before the burning cross like a high school drill team -- you expect them to spell out KKK on the field, which, had they done it, would have been a better payoff for the gag. And there's more, involving Penny and their seven daughters, of whom Ulysses fathered six.

In short, this is a film that has everything, by which I mean too much of everything. Somehow the Coens (they both write; Ethan produces and Joel directs) couldn't stop themselves. It's as though every idea, every line they thought of, every gag, every possible music cue, was thrown in and added to the mix, and it's both too much and too little. Too little, because most of their inventions don't get quite enough time or space to work properly; and too much because those inventions just aren't that witty. There's a three-hour movie in there, but the film runs just an hour and 45 minutes and it still seems long.

Moreover, there's a distasteful snobbery toward southern culture of the era. Turturro and Nelson act like cartoon hillbillies, with slack jaws and rolling eyes. And they jig and bounce on stage as singers to a point somewhere beyond embarrassment. Are we to see them as humans or as cartoons? The Coens can't seem to make up their minds; they want to have it both ways.

The film is partially redeemed by Clooney's performance as a low-rent Gable, forever looking to find his Dapper Dan hair pomade; and by Holly Hunter's brief appearances as his long-lost wife, now on the verge of marrying a seemingly more respectable suitor. John Goodman, who can do no wrong in a film, has his moment as a one-eyed bible salesman, the film's version of the cyclops; and Durning, as the crooked governor, is a pleasure too.

But the film keeps misfiring; time after time it undercuts the fun and our hope for the kind of wit and perception the Coens have given us before, by going back to slack jaws, buggy eyes, caricatured poses and accents that were offensive long before 'Li'l Abner.' You'll get the best of the film if you buy the sound track CD, which has more complete performances of some of the film's music, plus some songs that didn't make it into the final cut.