01. The Mysterious Death on the Underground Railway
Polly Burton assists in soving the case of a grl found dead on a seat of an underground train.
02. Five Hundred Carats
Inspecor Lipinski investigates the theft of a 500 carat diamond.
03. Cell 13
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.
04. The Secret of the Manifique
Laxworthy and two friends secure the safety of the plans for the first torpedo to be used by the French navy.
05. The Absent-Minded Coterie
Valmont has to help break a ring of counterfeiters.
06. The Sensible Action of Lieutenant Hoist
Lieutenant Holst of Copenhagen has to help a Russian countess who claims her brother-in-law aims to kill her.
07. The Superfluous Finger
Professor Van Dusen must find out why a young woman had a perfectly healthy finger cut off by the eminent surgeon Prescott.
08. Anonymous Letters
In turn-of-the-century Vienna, Dagobert Trostler investigates a poison pen case.
09. The Moabite Cypher
Dr Thorndyke has to decypher a code to stop a plot to assassinate a Russian Grand Duke.
10. The Secret of the Foxhunter
William Drew of the foreign Office investigates an unusual crime.
11. The Missing Q.C's
Charles Dallas is led into a strange and sinister adventure in the aftermath of a sensational murder trial.
12. The Looting of the Species Room
Gold disappears from the strongroom of the RMS Oceanic and its purser, Mr Horrocks, tries to discover what has happened.
13. The Mystery of the Amber Beads
Hagar the Gypsy sets out to prove that Detective Sergeat Grubber is wrong about who killed Mrs Arryford.