“I don’t know what I’m doing,” Philip Seymour Hoffman laments quietly to an optimistic, uncomprehending Michelle Williams in “Synecdoche, New York.” Hoffman, a playwright and recent recipient of the MacArthur Fellowship, is in the midst of an existential dilemma over the theater piece he’s fashioning with his prize money. Williams, his dimwitted lead actress-cum-love interest, responds with a mixture of empathy and idiocy: “That’s what’s so refreshing.”

From its opening moments, it may seem that screenwriter Charlie Kaufman’s directorial debut is treading water—the notion of the “author-in-crisis” is a thematic thread that Kaufman explored ad nauseum in his 2002 screenplay for “Adaptation.,” directed by Spike Jonze. For all its novelties, that film was a headache, a neurotic monologue whose paranoid refrains only compounded the pretensions of its obnoxiously self-conscious narrative loop.

But to say that “Synecdoche, New York” revisits, or even improves, upon the more problematic aspects of that film is to overlook the sheer depth and ambition of the creative vision for which it strives. More to the point, “Synecdoche, New York” has a place in the genealogy of Kaufman’s work only insofar as it takes the personal context of those earlier films and erases them.

The story itself is as complex as Kaufman fans have come to expect. Caden Cotard (Hoffman) immerses himself in his work to escape his failed marriage. His sudden, debilitating loneliness amplifies and resonates with his obsession with the various frailties of the human form—injury, lesions, seizures—all of which Caden suffers from at one point or another. The rapidity and ambiguity of these different ailments hint at a complex known as the “Cotard delusion,” whose psychological symptoms overlap with Caden’s.

Samantha Morton—like Williams later on—drifts in and out of the void left by his first wife (Catherine Keener), an artist whose runaway success brings her to Berlin with Caden’s first child. Time compresses and confuses; after the first half hour of the film, it’s unclear whether Caden’s family has been abroad for a few weeks or a few years, and characters seem to age indiscriminately and disproportionately to one another.

Meanwhile, Caden’s theater piece evolves from the abstract—a “pure, honest theater”—to a realized vision, to a new vision of reality itself. Actors’ daily performances take place under Caden’s watchful direction and the concave glass ceiling of the enormous warehouse he’s purchased to stage the piece. The set design becomes more elaborate as time goes on, evolving along with the piece into a façade-metropolis, where Caden retreats from the outside world. He even finds an actor to play himself.

Kaufman’s work has always defied classification. The internalized aspects of scripts like “Being John Malkovich” or “Eternal Sunshine of the Spotless Mind,” as well as the overt absurdity of those internal structures as they move through the story, leave the works themselves astride a prism of possibilities—comedy, drama, fantasy, and autobiography. “Synecdoche” flirts with all of these labels and deigns to dwell in their respective cultures from time to time, but ultimately stands apart as a movie about the deconstruction of a character by his environment.

At its heart, the story is fundamentally one of displacement. Caden is haunted by the ghosts of his wife and child—the people for whom he has become something of a ghost as well—and his search for them comprises the funniest, most adventurous and heart-rending portion of the film. The dialogue between performance and real life is so dense and cyclical that Tom Noonan (who plays Caden in the play and follows him throughout most of the film) goes so far as to lead Caden to his wife’s new apartment in New York, seemingly in order to research his role. “I want to follow you there and see how you lose even more of yourself,” Noonan says.

Noonan becomes a casualty of the increasingly blurred boundaries of reality and theater, killing himself when he realizes Morton’s character will never love him like she loves Caden. But by then, Caden is so swallowed up by his role as the director that he effectively barks dramatic criticism at Noonan’s corpse. It’s more than a tragedy—it’s a tragedy in tragic pursuit of itself. Every layer of the film is so kaleidoscopic and thoroughly disorienting as to constitute an experience totally unlike any other in contemporary mainstream American film.

But there’s more at work in “Synecdoche” than can be readily explained. Beyond the Brechtian overtones of its self-referential theater, aspects of magical realism abound, tempered but not undernourished. Transposition of a diary across time and space, animate flower tattoos that whither along with their host, and a burning house whose inhabitants tolerate and ignore it for decades all play roles in “Synecdoche, New York.”

The film is alive, changing and renewing itself, presumably with successive viewings, in a way that “Eternal Sunshine” or “Malkovich” only hinted at. To call Charlie Kaufman a unique voice in Hollywood would have been satisfactory four years ago. With “Synecdoche, New York,” however, Kaufman has staked his claim as one of America’s most important filmmakers.

—Staff writer Ryan J. Meehan can be reached at rmeehan@fas.harvard.edu.