After acquiring the film rights, Schlöndorff turned to Rudy Wurlitzer, who had written numerous screenplays, including "Two-Lane Blacktop" (1971), "Pat Garrett and Billy the Kid" (1973), and "Walker" (1987). Wurlitzer and Schlöndorff made several important changes for the screenplay. The story became less a political morality tale than a haunting narrative of personal destruction. While retaining the European settings and supporting characters, he changed the nationality of the protagonist, transforming Walter Faber into an American engineer. During the screenplay's development, Schlondorff visited Max Frisch at his Munich apartment, seeking out and receiving the author's guidance and approval for the significant changes being made to his story.