Lars von Trier (Breaking the Waves, Idioterne) ripped up the filmmaking rulebook and wrote his own rules with his manifesto for Dogme 95, becoming a hero among indie filmmakers everywhere. He's up to his old tricks again, except here he is goading Danish poet and sometime filmmaker Jorgen Leth, one of von Trier's heroes, into making a film by such an awkward set of rules, the "obstructions", that it will turn out "crap".

Why? Over pre-noon vodka and rich food, Lars teases his good friend that he knows him better than himself. And Lars believes that only by pushing Jorgen into making a "banal" film will Jorgen be forced to lose the cool distance that is such a characteristic of his art and reveal his real self. Jorgen, who turns out to be a great sport, nods, grins and makes notes.

Lars requests that Jorgen remake his 1967 film "The Perfect Human Being" a starkly shot, black-and-white artfilm that makes a drily humourous, anthropological study of two "perfect" (Danish) human beings. Lars seems to pluck his obstructions out of the air. Jorgen is talking about how much he is enjoying his after-meal cigar. Lars chips in by saying you will shoot the film in Havana (less a trip for Jorgen than most since he is Denmark's official representative in Haiti). He must also film with no more than 12 frames at a time without an edit (that's less than half a second), no props and so on.

As with the Dogme manifesto this tongue-in-cheek experiment into artistic endeavour is both playful and intellectually stimulating. The handheld filming that documents the process by which Jorgen comes up with his solutions is typically shaky, almost a device in itself to accentuate the slick finish of the set-piece films. Jorgen, who clearly wants to make anything but "crap", rises to the challenge returning with impressive solutions to the various different obstacles from Cuba, Bombay, and Brussels.