Bernhard Günter, formerly the criminal commissioner of Berlin’s main police directorate, opens a detective agency after the war. His first client is Britta Varzok, who wants to find her husband—a war criminal who “went underground” in Argentina. The moment Günter starts following the trail, he is brutally beaten. The doctor tending to him suggests that the detective recover at the estate of his friend, Dr. Gruehn, who is wheelchair-bound. By some strange coincidence, Gruehn turns out to be remarkably like Günter. Taking advantage of this, the doctor sends the visitor to Vienna to arrange the inheritance left to him by his mother. In Vienna, Günter is blackmailed and then accused of the murder of Britta Varzok, whom he finds dead. Realizing he has been set up, the detective decides to get revenge.