The Door with Seven Locks

Detective Dick Martin is leaving Scotland Yard. His final job is to bring in Lew Pheeney, wanted in connection with a bank robbery. When Lew confesses to trying to open a dead man's tomb, however, Martin has a mystery he must unravel. He races to find the connection between an attractive young librarian, a mad scientist and the vanished heir to a vast fortune, as everyone becomes entangled in a web of fraud, deceit, torture and murder.