Cannes reveals just how much interesting, ambitious and surprising work is being done, both in established centers of film production and in countries whose film industries have lain fallow or barely existed.

Mr. Linklater's other festival film, the Certain Regard Selection "A Scanner Darkly," based on a novel by Philip K. Dick, sends tendrils of anxiety in all directions. Is the war on drugs worse than the drug epidemic? Can you tell the difference? Is the government spying on us, or does our own paranoia make such a program redundant?