The book is a crime thriller written by Hans-Ulrich Horster in 1960. It tells the story of a serial killer who, after escaping from a psychiatric institution, meets a woman and her child. Despite this new connection, he continues to feel an uncontrollable urge to strangle women who wear red necklaces.
In 1962, the novel was adapted into a film of the same name, directed by Wolfgang Schleif and starring Klaus Kinski.
