IF SARTRE WAS RIGHT and Hell is, in fact, other people, then Albert Brooks has been on one long, hot journey for the past couple of decades. Only a handful of American filmmakers bother to intelligently explore the comic tortures of being human anymore, and no one quite plunges into these tortures with Brooks' gloriously excruciating zeal. Even Woody Allen, to whom Brooks' work as writer/director/performer is often compared, doesn't suffer the kind of keenly human embarrassments Brooks heaps upon himself. There is nothing remotely flattering or charmingly quirky about his degradations, which is why you're likely to hurt yourself laughing at them, and also why, of course, he is not as beloved an artist as he should be.

Brooks is the Schmuck with Ideals, an intellectual Everyman destined to fall on his own sword, usually to the accompanying guffaws of his singularly demeaning Greek choruses. Lost in America, perhaps his most consistent film, had disillusioned former ad man Brooks reduced to being a crossing guard in Arizona, tormented by adolescent boys on bicycles who circle him with taunts of "retardo" and "dumb Brillo pad fat head." In The Muse, his latest work, despairing screenwriter Brooks watches helplessly as his costly and supposedly heavenly source of inspiration (Sharon Stone) brings success to his cookie entrepreneur wife (Andie MacDowell), causing Wolfgang Puck to refer to him as "Mr. Fields."

With Brooks, it's the details that mean the most: "retardo," the appearance by Puck. The extra inch that he (and frequent co-writer Monica Johnson) sneaks into the material is usually the one that has you laughing the hardest years after seeing one of his films. When Brooks is shameless, he goes to places in your social and pop consciousness that you'd like to pretend you don't recognize. Few can forget that at the beginning of Defending Your Life, Brooks is killed in a head-on collision with a bus while giddily singing along to Barbra Streisand's cover of "Something's Coming" from West Side Story. Real Life, the mock documentary that was his first film, had him playing himself as an arrogant, insensitive filmmaker intent on capturing every last moment in the life of a typical American family. Presaging all the Real Worlds and Truman Shows to come, he held himself complicit in the media mire.

Better still is what has to be the crowning achievement in the Brooks canon of Letting It All Hang Out: the nearly 15-minute Quaalude scene in Modern Romance. Distraught after yet another break-up with long-time girlfriend Kathryn Harrold, Brooks takes two Quaaludes given to him by Bruno Kirby and slowly, hysterically unravels. From his initial insistence that he doesn't feel the drug's effects, Brooks uses long takes to build to the point where he is stumbling around his apartment, dancing in his bathrobe to Walter Murphy's cheesy disco hit "A Fifth of Beethoven," and calling a vaguely remembered old flame to tell her, "I have deep feelings for you." Brilliantly sustained and howlingly funny, the scene belongs on a very short list of comic tours de force, and it highlights the director's major contribution to cinema comedy: Albert Brooks is as brutal to himself as he is to society.

It's this brutal quality that is somewhat lacking in The Muse, despite the fact that you probably won't find a smarter comedy this year. Through the advice of successful friend Jeff Bridges, Brooks employs the services of Stone, a purported Divine Muse (as in, daughter of Zeus), showering her with gifts and a suite at the Four Seasons in hopes that she will inspire him to write a smash comedy for Jim Carrey. Everyone in Hollywood, it seems, is desperately using Stone, and there are mildly amusing, in-joke cameos by everybody from James Cameron to a hyperkinetic Martin Scorsese. Brooks is taking a wily and well-deserved stab at the superficial, grasping industry that has kept him second-string (there's a priceless bit that has him shamed by Lorenzo Lamas), but it's obvious that this time around the balance between Brooks as victim and co-conspirator is weighted heavily toward the former. After receiving an industry award of merit, his daughter asks him what a humanitarian is, and he casually answers, "Someone who's never won the Oscar." That's suitably cutting, but Brooks needs to take a bigger bite out of Hollywood, then have his character truly whore himself. The film, though, never goes full throttle in that direction, perhaps because in real life, with a new wife and child, Brooks has lost some of his vitriol.

No matter: The Muse will keep you laughing. Brooks will keep you laughing (he even successfully channels Stone's frantic, everything-but-the-kitchen-sink technique into a winning comic creation). He's done more than most artists to remind us that Hell may really just be ourselves.