Unknown assailants threaten the life of British scientist Dr. Ronald Fergusson. Only by chance does the attempt to shoot him in the street fail. Fergusson, who does not believe in police protection, hires private detective Weber for his personal safety. And time and again, the headstrong scientist makes it difficult for his bodyguard to fend off further assassination attempts. Despite being expressly forbidden to do so, he leaves the house. Full of bad suspicions, Weber looks for his client in the morgue, but Vivian, Fergusson's employee, doesn't know the dead man...