Sherlock Holmes confronts his deadliest enemy yet: a man who hates him, his creator, Arthur Conan Doyle. Holmes has deduced it wasn’t Moriarty, but Doyle, jealous of his popularity, behind the near-fatal attack on him at the Reichenbach Falls. Holmes, a notable rationalist, is further irked by being constantly linked with Doyle, the famous spiritualist. When two girls claim to have photographed fairies and Doyle believes them, this disgusts Holmes. He seeks to refute the pictures, but unlocks a deeper mystery surrounding the events at Cottingley. Can logic overturn belief?