Synopsis:

A thief, together with his accomplice, steals a cache of diamonds, but is then killed on the train which was to take him from France to Spain and the diamonds disappear. Convinced that the thief has told his daughter where they are, a masked man starts to threaten the girl that he will kill her unless she hands them over. The girl, who knows nothing about the loot, believes that it is her luckless boyfriend making the threats and flees to England with a doctor who has been courting her for some time. The boyfriend also arrives in England to search for the girl, but coinciding with his arrival, both she and the doctor’s wife are killed. But the killer, the masked man and the father’s accomplice are really the same man. Which one?