The Secret Killer (1965)

In the late 20's, Germany has high inflation rates and unemployment and the rise of the Nazi Party. In this scenario, in Dusseldorf, the worker Peter Kuerten, also known as The Vampire of Dusseldorf, commits nine murders. The weirdo Peter Kuerten is obsessed in the cabaret singer Anna and they have a love affair. Meanwhile he kills young women on the desert streets of Dusseldorf. One day, a man escorts Anna to her home and is followed by Peter. When he leaves her, the jealous Peter Kuerten kills him on the street. The Chief of Police Momberg is pressed by Berlin to hunt down the serial-killer since the victim was an industrialist.