"World's Greatest Dad" is a startlingly original vision. The movie is dark, funny and appalling, but it's also emotionally probing -- a bold mix of narrative elements that works brilliantly. As in his last film, "Sleeping Dogs Lie," writer-director Bobcat Goldthwait centers his plot on a shocking incident -- a teenager's death by auto-erotic asphyxiation. But like "Dogs," which used a brief bout of trans-species sex to trigger its story, this movie is all about subsequent repercussions, not the act itself.

Among other impressive things, Goldthwait has found a use for Robin Williams' often maudlin sweetness. Williams plays Lance Clayton, a lifelong aspiring writer who's never managed to get published. He's a timid high-school poetry teacher whose classes are most notable for their many empty seats. He's also carrying on a love affair -- or at least a sex affair -- with a pretty, young art instructor named Claire (Alexie Gilmore), although the middle-aged Lance has no more idea what she sees in him than we do.

Lance is a single dad who lives with his teenage son Kyle (Daryl Sabara) -- one of the foulest kid characters in movie history. Kyle is mean, hostile and abusive to everyone around him, not least his father. He hates music (thinks it's "gay"), hates movies -- hates everything, in fact, but the nastiest sorts of Internet porn, which he watches incessantly, hunched forward with a strap tied tautly around his neck. Catching him at this one night, Lance meekly attempts to have a fatherly discussion about it, but Kyle just snarls at him.

When Kyle finally takes his porn obsession too far, and chokes to death, Lance is left with a very embarrassing scene. So he tidies things up to make it look as if Kyle hanged himself. He even writes a suicide note for his son -- a long, melancholy message to all those the apparently misunderstood Kyle has left behind. Soon the suicide note shows up on the Internet, where it's seen by Kyle's schoolmates -- all of whom loathed him in life, but now realize he had a beautiful, sensitive side, too. Soon they're wearing Kyle buttons; Kyle posters appear. Lance, now inspired, begins churning out further "Kyle" writings. Before long book deals come pouring in, and offers for TV appearances. Lance is at long last launched as a writer.

One scene in particular vividly displays Williams' technical expertise as an actor. After Lance's book -- a collection of "Kyle"'s prose -- has been published, he's booked onto an Oprah-like TV show to promote it. Coached by one of the show's producers to "just go with it" if he feels himself starting to cry on-camera, Lance does indeed begin tearing up under the host's shameless prodding. What's remarkable about this scene is that Lance isn't actually crying -- he's having a hysterical giggling fit. The host and the studio audience see only the grief they want to see; but we see what's actually happening, and how seamlessly Williams keeps these two emotional states playing across his face. It's an extraordinary moment.

Lance finally has the literary acclaim he's always wanted, but of course it's second-hand. He also has the renewed affections of Claire, who'd been drifting off toward another, more popular teacher. But Claire is deeply weird, and Lance's only real connection -- a new one -- is with an old neighbor lady who shares his enthusiasm for marijuana and zombie movies. Where can all of this be going?

Goldthwait keeps the movie's unexpected twists coming all the way to the end -- a virtuoso feat. It's fitting that "World's Greatest Dad" was co-produced by another gifted writer-director, "Donnie Darko" auteur Richard Kelly. The movie is a true indie, made, no doubt, for practically nothing (in Seattle). But in a time of endless big-budget, inspiration-free cinematic recycling, it's a real find. In a modest way, it's got everything.

Don't miss Kurt Loder's reviews of [article id="1619193"]"The Baader Meinhof Complex"[/article] and [article id="1619160"]"Inglorious Basterds"[/article], both new in theaters this week.

Check out everything we've got on "World's Greatest Dad."

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