Like the Vietnam film that inspired it, “Hearts of Darkness” is a study of disintegration. As the production came unglued, almost everyone connected with it fell apart–beginning with the cast. In the documentary’s most startling sequence, a drunken Martin Sheen breaks down under the director’s lash. Moaning and babbling, he slashes his hand on a broken mirror, then screams at the off-camera Coppola: “You f—r!” Two grips drag him off, naked and weeping, to a shower. Later, after Sheen suffers a near-fatal coronary, we see him getting first aid and last rites. Cut to Dennis Hopper. He’s so stoned he can’t remember his lines, and when he does recall them he wants Coppola to explain the reasoning behind them. A grossly bloated Marlon Brando arrives without having read “Heart of Darkness,” the Conrad story on which the film is based. Midway through a hilariously indecipherable monologue, he blurts: “I swallowed a bug.” Then he lumbers off, announcing: “I can’t think of any more dialogue today.”

Coppola has even bigger problems: set-wrecking typhoons, a Philippine civil war, media sniping back home, looming bankruptcy and, worst of all, his inability to find an ending for his epic. As a 16-week shoot balloons into two years of agita, Coppola, like Conrad’s characters, begins slipping toward the outskirts of madness. It’s creepy eavesdropping on his despair. “My greatest fear is to make a really s—y, embarrassing, pompous film on an important subject,” he rails to his wife. “And I am doing it!” Later: “What I have to admit is that I don’t know what I’m doing.” Still later: “This film is a $20 million disaster… I’m thinking of shooting myself.” He may not be joking: there’s a close-up of him, gaunt and hollow-eyed, holding a pistol to his temple. All of this might rouse our sympathy if Coppola weren’t so self-obsessed. Following Sheen’s coronary, he tries to keep word of it from his critics back home by instructing an associate: “I want to hear everything is OK until I say Marty is dead. You got it?” This is a portrait of the artist as a whining, conniving, egomaniacal jerk.

So why would Coppola help make the documentary possible? Since his company owns home-video rights, he stands to make some money from it. But a colleague of the director reports that it was more a matter of his wife’s prodding and Coppola’s own fascination with his creative struggles. Whatever Coppola’s motivation, give him this: it takes a little craziness to make a masterpiece, and a lot of guts to reveal it.