An up and coming politician is caught in a compromising photograph taken by a maid, who turns out to be part of a sophisticated blackmail ring. When the girl is found murdered, he holds an incriminating old dueling pistol.

A group of crooks accidentally kill an elderly shop assistant while stealing the keys to the jewellery shop where she works. When his superiors think that the case is better handed over to Scotland Yard, the local detective inspector, Sparrow, decides to go solo to investigate the crime himself.

Based loosely on the real-life story of the World War I spy. The exotic dancer uses her contacts in European high society, along with her seductive charm, to collect military secrets during the war. She successfully plays both sides against each other until at last her deceptions catch up with her.