Rival gangsters from Chicago move to London and attempt to extort money from rich Britons.

A private detective tries to find out how and why some convicts have mysteriously disappeared from the prison of Dartmoor.

After an automobile accident, in which a man is unrecognizably burnt to a crisp, his wife's only able to confirm the corpse's identity by his talisman: a small, white spider. However, soon, there are more corpses walking around than at a comic con convention and every single one of them was a white spider sitting on or nearby the body.

Both Scotland Yard and an amateur American sleuth are tracking a master criminal known as The Frog. This moniker refers to the bulging-eyed mask worn by the evildoer, and is reflected by the frog icons painfully tatooed onto the forearms of his henchmen. The trail leads to the country manor of an enigmatic, steely-eyed nabob, whose repressed son has eyes for the artistes at the Lolita cabaret, and whose lovely daughter captures the fancy of both the American playboy and the villain himself. Murder, kidnapping and seduction ensue.

A strange, red circle appears on the neck of a man saved from the guillotine. What is its mysterious meaning? Tragically, it turns out to be something of a family curse, as each generation thereafter bears the same sign, which in turn leads to blackmail and murder.

A disfigured killer with glazed-over white eyes is doing the dirty work so that an insurance agent-doctor can get the victims' insurance money.