Famous investigator Harry Dickson is just back in London after some well-deserved holidays, and already Scotland Yard are seeking his help again, for there are very strange events afoot. A famous heiress and writer, Delphina Cruikshank, has vanished from a locked house. The corpse of an executed murderer has disappeared … while the doctor who was autopsying him was murdered. And Mysterion, Miss Cruikshank’s new character, may not be entirely fictional!

Harry Dickson’s skills were instrumental in getting blood-thirsty killer ‘the Red-Eyed Vampire’ arrested. The detective is invited to the small German town where the murderer was from to witness his execution. However, he cannot help but wonder whether somebody else was controlling the ‘Vampire’ before abandoning him. When an attempt is made to break into the condemned man’s cell the night before his death, Dickson knows that the investigation is not over yet …

Frederic Hamilton, an aging millionaire and philanthropist, calls upon Harry Dickson to investigate most curious facts. For some time, he has been having strange dreams in which he appears before a mysterious court – eleven masked judges who accuse him of despoiling Humanity. Now, his latest dreams have included physical torture … and the pain is still present when he wakes up! Dickson and Superintendent Goodfield travel to Hamilton’s residence, but their mission quickly turns into a nightmare …