During World War II, three German soldiers are withdrawn from combat when one of them, Stroszek, is wounded. They are assigned to a small coastal community on the Greek island of Kos while Stroszek recuperates. The men become increasingly stir crazy in their uneventful new assignment. Stroszek eventually goes mad.
The fortress which gives the film's main setting is a real 14th-century fortress built by the Knights Hospitaller. Herzog's grandfather, Rudolf Herzog, lived and worked for several years as an archaeologist at this site, and published translations of the ancient Greek engravings which appear in the film. The old Turkish man who appears in the film with a written translation was the last surviving worker from Rudolf Herzog's archaeological project.
During several shots, Peter Brogle could only be filmed from the waist up after he had been injured in a tight-rope accident and spent several months in a walking cast. The man who appears as a pianist in one scene is keyboardist Florian Fricke of Popol Vuh, who composed and performed the music for many of Herzog's later films.
Many of Herzog's later films reference elements of Signs of Life. The Enigma of Kaspar Hauser includes a scene with a hypnotized chicken, and the main character's name is given to Herzog's film Stroszek. The Wild Blue Yonder contains a shot of a valley of windmills.