A curious young helmer tracks down the profanity-spewing subject of a two-decade-old viral video.

A curious young helmer tracks down the profanity-spewing subject of a two-decade-old viral video with results at once scabrously funny and uncomfortably poignant in “Winnebago Man.” Festival kudos (including the docu prize at Sarasota and the audience award at CineVegas) suggest the pic’s cautionary message about unwelcomed cult stardom could transcend its hipster trappings and garner modest theatrical biz ahead of guaranteed ancillary action.

During a sweltering 1988 Iowa fortnight, a loquacious fellow named Jack Rebney wrote and appeared in a series of industrial films touting the eponymous manufacturer’s line of recreational vehicles. Whether it was the heat, the swarms of insects or Rebney’s own hair-trigger temper that got the best of him is unclear, but a four-minute assemblage of outtakes prepared by the vengeful crew find the huckster swearing an eloquent blue streak as he flubs lines and swats flies.

“Willya do me a kindness?” is one of the few printable catchphrases to have emerged from the tape, known most commonly as “The Angriest Man in the World.” Legend holds that director Spike Jonze gifted friends with dubs over the holiday season, and since it was uploaded in 2005, chunks of Rebney’s blustery tirades have seeped into popular culture (Ben Affleck quotes the rant in “Surviving Christmas,” of all films).

As Steinbauer prepares to track down the elusive Rebney, he considers other victims of viral videos, including the poor “‘Star Wars’ Kid,” whose uncoordinated swings with a fake lightsaber were uploaded by “friends,” and Aleksey Vayner’s video resume “Impossible Is Nothing,” which was posted without his knowledge and subsequently spoofed by Michael Cera. Academic Douglas Rushkoff and helmer Alan Berliner also weigh in on the phenomena.

When Rebney finally is located in a Sierra Nevada cabin, the pic strains to accommodate the deeper issues stirred by the discovery. At first mild-mannered, Rebney, now nearly blind from glaucoma, appears to play up to his rep via an at-times awkward irascibility. Even more uncomfortable is a trip to the traveling Found Footage Festival in San Francisco, where Rebney is fawned over like a rock star by self-consciously in-the-know twentysomethings.

By inserting himself into the process, Steinbauer gets points for being brave enough to stick with the story. Yet there are as many questions as answers at the fade, most involving Rebney’s lone friend and true feelings about his fame.

Tech aspects are fluid.

Winnebago Man

Production

A Bear Media presentation, in association with Field Guide Media, of a Do Me a Kindness production. Produced by Joel Heller, James Payne, Malcolm Pullinger, Ben Steinbauer. Directed by Ben Steinbauer. Written by Malcolm Pullinger, Steinbauer.

Crew

Camera (color, HD), Bradley Beesley, Berndt Mader; editor, Pullinger; music, Andrew Hoke, Taylor Holland; sound designer, Chris Keyland. Reviewed on DVD, Sydney, Australia, June 5, 2009. (In Silverdocs Film Festival, Silver Spring, Md. -- Silver Spectrum. Also in SXSW, Hot Docs, Sarasota, CineVegas film festivals.) Running time: 87 MIN.

With

Jack Rebney, Ben Steinbauer, Keith Gordon, Douglas Rushkoff, Alan Berliner, Tony Dahle.
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