Desius Heiss is the French-born owner of an antique shop on Sly Corner who bears a grudge against society. His imprisonment and tortue on Devil's Island has left him with scars down his back from repeated whippings. With little care for the authorities, Heiss has allowed his shop to become a center of criminal activity and enjoys a secret career as a receiver of stolen goods. His daughter, Margaret, is a violin virtuoso and knows nothing of her father's criminal activities. But when the antique shop's assistant, Archie Fellowes, discovers the illicit trade in stolen goods, he threatens to blackmail Heiss. Desperate to keep his criminal activities a secret from his dauther, Heiss decides to silence the blackmailer. But when Inspector Robson takes a close interest in the shop at Sly Corner, Heiss must stay one step ahead of the police if he values his neck.