Timothy Treadwell spent 13 years of his strange, solitary life living with the wild grizzly bears of Alaska. An amateur naturalist and fully certified eccentric, he was possessed by delirious aggrandizement, imagining himself the sole defender of the great predators, a “kind warrior” in the battle for their survival. From the evidence of “Grizzly Man,” he seems to have accomplished very little in concrete terms. But, then, the evidence in this case is of a most unusual kind.

During the last five years of his “expeditions,” Treadwell brought along a video camera and logged more than 100 hours of footage: nature photography, tour-guide monologues, intimate confessions, raging tantrums. With his floppy blond hair, surfer-dude looks, and fey, goofy demeanor, he comes off like a hippie Andy Dick with a touch of Mr. Garrison from “South Park.”

Much of the footage consists of irrepressible, over-the-top effusions of love for his animal friends (“I love you, Mr. Chocolate! I love you! I love you!”), but there’s an undercurrent of anxiety to his enthusiasm, a touch of madness. Over the course of years, his already tenuous grip on reality begins to slip through his fingers.

From this raw – sometimes bracingly raw – material, Werner Herzog has fashioned an unnerving documentary portrait of a man who went to the limit of humanity and beyond, “a film of human ecstasies and darkest inner turmoil.” While Treadwell’s video antics are ostensibly pitched to a public audience, he is, as Mr. Herzog observes, the director, star, and hero of his own private nature adventure.

It is a movie with the darkest of endings. In October 2003, Treadwell and his girlfriend were mauled to death, then devoured by a grizzly. The most sensational detail of this sensational story is the existence of an audiotape that recorded the sounds of their death. Mr. Herzog appears on camera only once, listening to the tape on headphones. He finds it intolerable, and turns it off.

Treadwell was a failed actor – he nearly got the Woody Harrelson spot on “Cheers” – with major drug and alcohol problems. His blessed out exile to the grizzly worlds was both a form of salvation and a radical rejection of social life. Friends and colleagues remember how he took on the body language and behavior of the grizzlies. It was as if, says Mr. Herzog, “there was a desire in him to leave the confinements of his humanness and bond with the bears.” Like many a Herzog hero, Treadwell has “reached out, seeking a primordial encounter, and in doing so he crossed an invisible borderline.”

“Grizzly Man” crosses a boundary or two of its own. The movie refuses to answer the questions it raises. Was Treadwell a holy fool or just plain foolish? An inspired conservationist or a complete idiot? His usefulness in the wildlife reserve is debatable. Exposing the bears to constant human contact may have done more harm than good.

Statistical evidence suggests that Treadwell’s crusade against poachers was a drama based more in his imagination than in reality. As for the spiritual dimension, Treadwell’s intimate communion with the bears – a form of narcissistic exceptionalism – violates centuries of native Alaskan respect for the domain of the great beast.

None of that particularly interests Mr. Herzog, a filmmaker who thrives on the romance of extreme human behavior. There has never been a documentarian less concerned with “making a case.” Facts are not stupid things so much as platforms for his own metaphysical musings. His imagination is transformative, metamorphic: He poeticizes everything. The results can be magnificent and maddening. “Lessons of Darkness” turned the burning oil fields of Kuwait into a vision of apocalypse that would have boggled the mind of Blake. In “The White Diamond,” the best of his recent documentaries, the entire universe is telescoped into a drop of water. These are great feats of the eye and mind, but when, in “Grizzly Man,” he flies a helicopter over a glacial wasteland and finds in “this landscape in turmoil” a metaphor for Treadwell’s “soul,” we’ve arrived at a kind of Wagnerian camp.

To what extent is Kuwait, Treadwell, or anything else the subject of a Herzog documentary and to what extent the pretext for Herzogian leaps into the void? Does it matter? The question is relevant insofar as we find ourselves questioning the authenticity of the essay. Mr. Herzog summarizes “Grizzly Man” as presenting “not so much a look at wild nature as … an insight into ourselves, our nature.”

No doubt about that: Treadwell offers an enthralling perspective on mankind’s limitless capacity for self-invention and self-delusion. But I’m not sure it can be said that Treadwell stands in profound revolt against “that same civilization that cast out Thoreau from Walden and drove John Muir into the wild.” Nevertheless, if such a thing is said in Mr. Herzog’s inimitably portentous voice (a heroic German confrontation with American vowels, approached as a set of thick, stubborn things to be scooped out by heavy movements of the tongue and jaw), then it will sound with a certain nutty grandeur, no matter how spurious.

Look elsewhere for the subtle gesture. This is the place to watch the great, ragged swipes of a man who believes “the common denominator of the universe is not harmony but chaos, hostility, and murder.” There’s more than one half-mad grizzly man in this movie, and may he never come back from the wild.

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It’s a shame Werner Herzog didn’t direct “Asylum,” an overwrought gothic romance replete with anguish, madness, adultery, treachery, psychic angst, bohemian squalor, and bad mothering. Alas, Patrick McGrath’s unnerving novel has been adapted for the screen by two of the bluntest chaps in the business. The screenplay is by Patrick Marber, the boring misanthrope who brought us “Closer,” and the director is David Mackenzie, auteur of the glum, dumb, unbearably pretentious “Young Adam.”

Natasha Richardson is Stella, the freethinking wife of an uptight shrink (Hugh Bonneville) newly employed at an asylum for the criminally cliched run by Peter Cleave (Ian McKellen), a nefarious ponce. As she wanders the grounds looking for a way to express the depths of her soul (or maybe just get laid), Stella sets eyes on a deranged sculptor with amazing abs (Marton Csokas as Edgar). No matter that he’s locked up for gruesomely murdering his wife in a fit of jealous rage – he’s nice to Stella’s young son and has a delicious way of ravishing her on the floor of the greenhouse.

As you can imagine, things get complicated. Just how complicated had a good number of people at the preview screening I attended howling with laughter by the third act. “Asylum” imagines itself an inquiry into very serious subjects: the dangers of passion, the cruelty of patriarchy, the thin line between sanity and madness, and how that line may be drawn and erased by institutional power. But the details are all sloppy, so nothing adds up.

Mr. Mackenzie is careless with his actors, never noticing the way they spin in their formulaic roles, unable to find the right traction for their scenes. The production design is as cliched as the characters: Edgar’s dilapidated atelier is preposterous. As in “Young Adam,” Mr. Mackenzie has worked out a specific sordid drabness of atmosphere, but it just hangs on the surface of things. “Asylum” has no inner development; everything is applied from the outside in. It’s not enough to drive you crazy, but you might start hearing voices in your head: “Walk out of the theater.”