What appears at first to be the final confrontation between master detective Sherlock Holmes and his perennial arch-enemy, Professor Moriarty, proves to be more than even Holmes bargained for: he finds himself facing an old-but-new enemy whose determination to outwit and destroy the great detective is even greater than before. The ensuing intellectual cat and mouse games between these two larger-than-life figures form the exciting centrepiece of this original musical based on Sir Arthur Conan Doyle's characters.