The Five Obstructions

The Five Obstructions is a 2003 Danish documentary film directed by Lars von Trier and Jørgen Leth. The film is conceived as a documentary, but incorporates lengthy sections of experimental films produced by the filmmakers. The premise is that Trier has created a challenge for his friend and mentor, Jørgen Leth, another renowned filmmaker. Lars von Trier's favorite film is Leth's The Perfect Human, and Trier gives Leth the task of remaking The Perfect Human five times, each time with a different "obstruction" (or obstacle) imposed by Trier.

Synopsis: Wikipedia, CC BY-SA 4.0