The Rivals of Sherlock Holmes

Polly Burton assists in soving the case of a grl found dead on a seat of an underground train.

Professor Van Dusen, the Thinking Machine, boasts that he can think his way out of a prison cell. When he is locked up he is given the chance to prove that he can escape by the power of his mind alone.

Valmont has to help break a ring of counterfeiters.

Professor Van Dusen must find out why a young woman had a perfectly healthy finger cut off by the eminent surgeon Prescott.

Dr Thorndyke has to decypher a code to stop a plot to assassinate a Russian Grand Duke.

Charles Dallas is led into a strange and sinister adventure in the aftermath of a sensational murder trial.

Hagar the Gypsy sets out to prove that Detective Sergeat Grubber is wrong about who killed Mrs Arryford.