Un Chien Andalou remains a startling artifact suggesting ways in which film can express the subconscious. The result of Luis Bunuel's collaboration with Salvador Dali, the 17-minute, 1929 film was designed expressly to shock and provoke. Opening with the canonical eyeball-slashing sequence and divided into baffling "chapters", this is a work of art obsessed with religion, lust, decay, violence, and death. Un Chien Andalou isn't simply one of the great works of the surrealist movement, but a segment of cinematic DNA that irrevocably altered the aesthetics of film. In its tangled corridors you find the seeds to the disappearing-mouth bit in The Matrix, the carcasses strewn through Peter Greenaway's A Zed and Two Noughts and pretty much the entire oeuvre of David Lynch.