Modern art house director Lars von Trier spends a few months torturing his idol, the experimental documentarian Jørgen Leth, in a variety of cruel and unusual ways. As the taskmaster of a twisted private game, von Trier compels Leth to painstakingly recreate his 1967 surrealist short, The Perfect Human, on five different occasions with a gauntlet of handicaps and restrictions. A shoot might require that he employ no more than twelve frames between cuts or travel across the globe, and Leth is merrily game for it all.

Ultimately, the goal is to strip the film down to the core and unravel its mysteries - many of which were seemingly lost to the director himself - and it does successfully dip a few toes into those waters. But as Leth gets more films under his belt, the obstructions become more passive, quizzical and vague. By the time we arrive at the delivery of his final film, a light, enjoyable concept has become too heady and analytical for its own good, and neither man is smiling with the kind of vigor they were at the outset.