Under its flickering postmodern stylizations, its twitchy narcissism, its obsession about its author's own preciousness, "Adaptation" decodes into one thing: It's about someone trying desperately to do something he can't.

How universal is that? It's what I'm doing right now in a room full of people doing the same thing, and all you boys and girls out there looking at the newspaper from the outside in, you can't do anything either and you do it anyway. As he does, as I do, as you do, here's what happens: You start, you grunt, you stop, you start, you quit, you hate yourself, you daydream, you try again, you beat yourself up, you beg for mercy, you pray to God, you denounce God, you contemplate suicide, you go to the bathroom, you go to the bathroom even though you know you don't have to go to the bathroom, and somehow the end product of all this internal combustion is what most of us produce most of the time: the best we could do, no more, no less, goodbye, I need a drink.

To my knowledge nobody has made a movie on this topic before. I certainly hope no one ever does again. But . . . "Adaptation" is simply brilliant.

Let's define cases. Technically, procedurally, practically, "Adaptation" can be described thus: It is about a screenwriter having trouble writing a screenplay for the very movie that you are watching. He knows what it's supposed to be; it's supposed to be a straightforward film version of a nonfiction book by Susan Orlean, a New Yorker writer, called "The Orchid Thief." But he just can't find a structure on which to build his edifice, or some kind of angle into the material, and as he sinks deeper into despair, his mind begins to wobble this way and that in comic incandescence, a spluttery nova of self-loathing, doubt and nihilistic impulse. And of course -- this is always the worst part for anybody -- he looks out at a world blissfully unaware of his agony, where people seem to be succeeding without a whisker of effort. That's an illusion, of course. But it's an illusion he loves, because it allows him to hate himself so much more passionately.

I thought it was a writer's movie at first, because it was so familiar, and having been sentenced to death by the ASDFGHJKL row of keys many a time, I connected with it at a primal level. But what it describes isn't peculiar to writers; it's peculiar to humans, if they have an IQ over a grapefruit's and a yearning sense that somehow, somewhere, all this should be better but most of all they should be better.

Our hero -- also our writer -- is Charlie Kaufman, the screenwriter of "Being John Malkovich," who presents himself via this script not as a brilliantly successful, highly original screenwriter but as a total loser. Fat, balding, self-hating, lazy, inefficient, riven with sexual fantasies and ripped by sexual inadequacy, timid, nervous, infantile, a chronic masturbator. But you have to say this for him: He sweats less than any fat guy I know, although he does sweat quite a bit.

The movie takes place no place, and everyplace: in reality, in fantasy, in history, all more or less interchangeably. It opens -- this has to be a first -- on what I take to be a fictionalized version of the "John Malkovich" set where Malkovich, ever the good sport and in this case actually playing John Malkovich on the set of "Being John Malkovich" (boxes within boxes!), delivers a blistering warning to the other cast members about hurrying up, and it's exactly the sort of harshness that would depress a sensitivo like Charlie Kaufman. Except that's not Charlie Kaufman. That's Nicolas Cage, playing Charlie Kaufman.

Soon enough Kaufman's in hell -- that is, his real life. Failures dog him. Soon enough, he's alone in his room with a typewriter. Mission Impossible: to adapt the Orlean book, which is about a rogue botanist named John Laroche (brilliantly played by Chris Cooper), who in his clever way both loved wild orchids and coveted them. He was busted over and over again, but kept sneaking into the Florida Everglades to sneak the endangered plants out, not for profit but for . . . well, collectors will know why.

The movie -- directed by that other "Being John Malkovich" cleverboots, Spike Jonze -- flutters between the struggling Charlie and, three years earlier, the struggling Orlean (Meryl Streep, and it's so nice to have her back), launched on her journalistic seduction of Laroche but at the same time aware that she is also being seduced.

In fact, every character in the movie strains after an ideal that is ultimately unattainable. Every character, that is, except for the made-up one: Charlie's twin brother and foil, Donald (Cage also, of course), who is Charlie without the talent or the hang-ups. He has no self-doubts, he has no irony, he is charmingly, aggressively superficial, and success just, duh!, happens to him. Sponging off his brother, he declares himself a screenwriter, too, and keeps asking sophomoric questions that further infuriate Charlie. Meanwhile, Donald is effortlessly picking up chicks, having sex, meeting people, learning, taking the kind of screenwriter-wannabe seminars that a professional would despise, and . . . selling a thriller script.

Frankly, I was happy to learn that there is no Donald, that he is an artifice of "Adaptation" who serves merely to spotlight Charlie's inadequacies (though the movie doesn't reveal this). People like Donald shouldn't succeed, though all too frequently they do. Anyhow, this is a fabulous if fragile contraption, and one worries if Kaufman has the chops to bring it in for a landing.

The news is, well, sort of. He's onto something here, though I fear some viewers won't quite catch it. The movie turns into exactly what Charlie has desperately been trying to avoid: that is, into Every Other Movie. In other words, though he cannot admit it, at a certain point he has to yield to formula, even in fantasy, and thus "Adaptation" turns into adaptation: Thriller aspects are thrown in, a car chase or two, a shootout, and each of the characters we thought was real is suddenly a movie cliche. Charlie even has an epiphany at the end and is a Sadder But Wiser man. I hate it when that happens.

Not a great ending, but not a collapse either. Still, the movie is surely the most creative trick of the year and grimly funny throughout, until the change of tone at the conclusion. But as an act of pure audacity, it's got some cojones you wouldn't believe.

Adaptation (114 minutes, at area theaters) is rated R for profanity and drug use.

Doubled over: Nicolas Cage plays twins Charlie and Donald in Charlie Kaufman's fun-house-mirror of a movie about his own ordeal of having to write a screenplay.Nicolas Cage as a neophyte screenwriter in a movie about screenwriting.Meryl Streep plays New Yorker writer Susan Orlean.