Penelope Tredwell needs a sensational new story or her magazine, the Penny Dreadful, will go under. So when a mysterious letter arrives, confessing to the impossible crime of stealing the Crown Jewels, Penelope thinks she has found a plot to enthrall her readers. But Penelope begins to suspect the mastermind behind the letter could be real. Can she solve the mystery and keep the true identity of Montgomery Flinch a secret?