London 1885. A gang of lady thieves is targeting Piccadilly's wealthy shoppers and no one seems able to stop them. As frustrations build, the body of a young woman is pulled from the River Thames. Reporter Penny Green has a lot to write about, and she faces a new challenge when a stranger approaches her with a riddle. Could it lead to a killer? Time is running out for Penny - her impending marriage to Inspector Blakely signals...