Inspired by a famous 1971 psychological experiment, Oliver Hirschbiegel's German-language movie The Experiment finds a group of 20 volunteers randomly divided into 12 prisoners and eight guards and asked to play out their roles for a fortnight while scientists study their reactions. A conflict arises between undercover reporter Fahd (Moritz Bleibtreu), a con with a hidden agenda, and the apparently mild-mannered Berus (Justus von Dohnanyi), a guard with a megalomaniac streak. The film begins as a psychological drama as ordinary people settle into the game, with joking displays of resistance by the "prisoners" greeted with increasing brutality from the "guards," but detours into suspense and horror as Fahd, who needs the experiment to get out of hand in order to make his story more saleable, deliberately ratchets up the tension between the factions only to see the situation spiral nightmarishly out of control as various test subjects in both camps edge closer to snapping. With a terrific display of ensemble acting and unforced use of the popular claustrophobic semi-documentary look, Hirschbiegel's movie takes its time to get underway, with apparently irrelevant cutaways to Fahd's outside girlfriend (Maren Eggert), but works up to a powerful second half that delivers a sustained symphony of psychological and physical anguish. --Kim Newman