Photo model Monika Stange is found murdered in her apartment in a major West German city. Detectives Bentheim and Laube find rough diamonds hidden in the apartment. The trail leads to a racketeering ring and the influential industrialist Dr. Vogelsang. The latter is not prepared to get involved in the murder case under any circumstances and refuses to testify. Inspector Laube tries to solve the case without his colleague.

Eberhard Esche
as Kriminalassistent Bentheim

Barbara Brylska
as Hanna Stern

Herbert Köfer
as Kriminalinspektor Laube

Helga Göring
as Lydia Amberger

Horst Schulze
as Dr. Ingo Vogelsang

Lilo Grahn
as Gitte Moosbauer

Angelika Waller
as Monika Stangel

Joachim Tomaschewsky
as Herr Brösel

Karl-Richard Schmidt
as Peter Lacour

Rolf Ripperger
as Dr. Sauer