Marking Ingmar Bergman's debut as screenwriter and directed by Alf Sjöberg, this expressionistic crime of passion revolves around a young student, Jan-Erik (Alf Kjellin), his sadistic Latin teacher, nicknamed 'Caligula' (Stig Järrel), and a newsagent assistant-cum-prostitute, Bertha (Mai Zetterling). When Jan-Erik assists the drunken Bertha, he becomes her lover. Bertha is, however, terrified of another man, whom it becomes clear is terrorising her. When Jan-Erik finds Bertha dead, he accuses Caligula of being responsible. The themes of creaticity, mentors and oppressive authority, which would become Bergman's trademarks, are staked out in this semi-autobiographical work.