The Brown Bunny is a film by maverick actor/director Vincent Gallo that had its world premiere at the 2003 Cannes Film Festival, where it played in competition. Critical reaction was so hostile that the film quickly became labelled the worst in the festival's history, and many journalists even questioned the entire festival's artistic direction in admitting it in the first place.

Warning: Wikipedia contains spoilers

The film is a rambling odyssey about a motorcycle racer (played by Gallo) who undertakes a cross-country van drive in search of his former lover. The road scenes received especially heavy ridicule, consisting as they do of lengthy unbroken shots out the van's windshield, and one sequence in which Gallo parks the van and washes it, which plays in real time.

But the strongest outrage was reserved for the film's final scene, in which Gallo's character finally meets up with his ex-lover (Chloë Sevigny), and she performs fellatio upon him on camera.

The screening of the film at Cannes, where audiences will openly let their displeasure be known with loud boos and catcalls, was a fiasco, reportedly bringing Sevigny to tears and provoking a humiliated Gallo to apologize for making the film. Upon his return to America, however, Gallo took a defiant stance, defending the film and denying his apology. A war of words then erupted between Gallo and popular critic Roger Ebert, with Ebert writing that he had been more entertained watching his own colonoscopy than by The Brown Bunny, and Gallo retorting by calling Ebert a "fat pig."

Ironically, the outrage and hysteria surrounding The Brown Bunny meant it ended up being the most-talked about film of the festival—even more so than the eventual Palme d'Or winner, Gus van Sant's Elephant, and Lars von Trier's highly-anticipated Dogville—creating a mystique that some think may enhance its likelihood of securing US distribution.

A shorter, re-edited version of the film played later in 2003 at the Toronto Film Festival, and while not receiving the highest praise, also did not garner the level of derision the Cannes version did.