Not only did Sherlock Holmes survive the Reichenbach Falls, but he has a son, Sebastian, just graduated from a top European university, and itching to prove himself more than his famous father's equal. The opportunity presents itself in the run up to the First World War, when his uncle Mycroft, a member of the cabinet, introduces him to the First Lord of the Admiralty, an ambitious and bullish young tyro by the name of Winston Churchill. Rumour has...