Jews making fun of Jews, with affection and without, have provided some of the most savagely funny American art of the past 50 years. From Saul Bellow to Philip Roth, from WoodyAllen to Larry David, the tradition of mockery from within has been a reliable source of comedy and controversy alike, as well as a fascinating inquiry into the ongoing conflict between Jewish tradition and assimilation.

A Serious Man, the new film by Joel and Ethan Coen, is a bold and unexpected entry into this tradition of Jewish mischief, one based as much in metaphysics as in farce. It's no surprise that the authors of The Big Lebowski, Raising Arizona, Fargo, and Barton Fink should make a movie this funny—even their bad movies are funny (not counting The Ladykillers). But A Serious Man plumbs depths even major Coen devotees might not have imagined were there. It's not a departure, exactly—except in the way all their films are departures. It's an expansion, a magnification, a breakthrough. Yes, like all their movies, it's kind of a big joke, but a joke with the darkest punch line ever. The Coen brothers, who for 25 years have been called cold formalists with more interest in Steadicams and storyboards than in human characters, have made a movie about the twilight of the Jewish soul.

One of the pleasures and frustrations of watching a Coens movie—much like watching Claire Denis or reading Joan Didion—is trying to figure out what exactly is really going on while all that talent whizzes by. Their prodigious stylishness masks their true identity as master subtextualists. However recognizable a given film's genre constraints might be, the real story is almost always beneath the story. A Serious Man plays out as a sort of almost-modern-day Jewish folktale about a suburban schlimazel named Larry Gopnik whose life is on the verge of crumbling. A physics professor who might not get tenured (and who may or may not be getting bribed by a flunking student), a husband whose wife wants a divorce so she can remarry immediately (her oily lover wants everyone to be friends), a father whose totally assimilated kids are only interested in F Troop and nose jobs (they also steal his money to buy pot and join the Columbia Record Club), and a brother to a true loser (he's always in the bathroom draining his sebaceous cyst or getting arrested for gambling and sodomy)—Larry is beset by evidence that his dream of being a good guy with a good life is not coming true. He turns first to mathematics and then to his faith for solace, seeking the counsel of three rabbis whose advice ranges from banal ("Things aren't so bad: Look at the parking lot, Larry!") to inscrutable ("Helping others: couldn't hurt!"). But the more desperate he gets, the less comfort he finds in his old reliable rituals. Then, just when everything looks grimmest, those very rituals restore order—just before everything really unravels.

All this would feel like a traditional Coen brothers dark comedy if not for certain formal and tonal elements hinting at something more numinous in the film's design. It opens with a fable set in the old country in which a young couple is visited by a man the wife insists is a dybbuk (a body inhabited by an evil spirit turned away from hell). As the scene shifts to 1967, you keep expecting to return to this eerie, unresolved prologue, until its unresolvedness emerges as its clear purpose. Then there's 1967 itself—not exactly an insignificant year for the history of America or for modern Judaism, and not exactly the kind of detail the Coens would choose at random. Though no mention is made of the state of Israel or the Six-Day War (always subtext), Larry's plight has everything to do with the changing nature of Jewishness and the incompatibility of the old ways with his modern problems—not to mention with gentile America, in the shape of his deer-hunting, catch-playing, lawn-mowing neighbor who clearly hates him. When the neighbor is around, the film almost feels like a Jewish response to American Beauty. Instead of watching Kevin Spacey play midlife crisis, you see an actor no one's heard of (Michael Stuhlbarg, totally brilliant) play Job. But in Coenworld, Job gets to watch everything he's ever believed become obsolete, then pay for his rival's funeral. Funny.

It doesn't take a rabbi to see that A Serious Man is about the end of faith—not God faith as much as faith in the formalities of faith as a repository for life's unanswerable questions. Larry's doubts signal massive turmoil ahead, but they also feel like a cause for hope. Almost. Given all the binary talk we've been hearing about faith and reason for the past several years, the scope of the Coens' epistemological inquiry is startling. And bleak. And hilarious. And very Jewish.