Deathmaker (1995)

1924. Hanover, Germany. A salesman, Fritz Haarmann (Gotz George), confesses to having killed and dismembered 24 young men. Professor Ernst Schultze (Jurgen Hentsch) is commissioned to prepare a psychiatric report to determine whether or not Haarmann is of sound mind to stand trial for his crimes. In August, 1924, his six week examination begins in the Gottingen Provincial Mental Asylum. During the interrogation, Haarmann's madness is slowly revealed, as he details the motives and methods of his murderous acts. This is the true story of the most infamous mass murderer of the 20th century...