A war hero, invalided home from Afghanistan, meets a strange but charismatic genius who is looking for a flatmate; it is London, 2010, and Dr Watson and Sherlock Holmes are meeting for the first time. A string of impossible suicides has Scotland Yard baffled - and only one man can help.

Blackmail threatens the monarchy and Sherlock is about to meet the woman who beats him.

Two years on from reports of his Reichenbach Fall demise, Sherlock resurfaces as London comes under threat of a huge terrorist attack. John, though, has mixed feelings – he's delighted by the return of his best friend, but harbours worries that the consulting detective's reappearance will have an adverse affect on his settled domestic life, in particular his romance with Mary Morstan.