Hound suspects Professor Moriarty for the rising counterfeit money problem in London, but is unable to find any leads until a little girl comes asking Hound to help her find her father.

Professor Moriarty thinks he has found a weakness in Hound, his land lady Mrs. Hudson, and so sets about kidnapping her, but things don't go as he planned.

A little girl named Polly pickpockets a gem Professor Moriarty has just stolen, and he is determined to stop at no end to get it back.

The Royal Navy asks Hound and Watson to help them recover a submarine stolen by Professor Moriarty.

Someone has been sabotaging England's new Air Mail postal service to Europe, and it's up to Hound, Watson and Mrs. Hudson to find out who.

Sherlock Hound and Doctor Watson are asked to investigate the disappearance of twenty Sovereign Gold Coins from a specially constructed safe.