A radio-serial in ten instalments, adapted by Jack Inglis from the novel "The Gang-Smasher" by Hugh Cevely with Ivan Samson as John Martinson, Eileen Erskine as Sylvia Brown and Carleton Hobbs as Tortoni.

Sylvia Brown and her brother have fallen foul of a murderous gang of jewel thieves called the Tortoni gang. John Martinson, his man-servant Bond, and an American detective - J. D. Peters - are out to smash the gang. Tortoni's identity is a mystery even to his gang. He gives his instructions by wireless, with his own wavelength and signature tune. His principal assistants are Ricketts, Schluyter, Costello, and the Comtesse de Varenne - a cosmopolitan bunch of rogues.
Their intention is to steal the jewellery belonging to Elsie Somerville, a film star, who is in occupation of Marden Castle in Sussex with her so-called secretary, a Russian called Igor Volkieff. The gang have captured John Martinson, Elsie Somerville, and Professor André, are holding them in Marden Castle and are trying to force them to disclose where they have hidden the jewels.