"The Adventure of the Empty House" is the first Sherlock Holmes short story of the 13 collected in The Return of Sherlock Holmes written by Sir Arthur Conan Doyle. Public pressure forced Conan Doyle to bring Holmes back to life, and explain his apparently miraculous survival of a deadly struggle with Professor Moriarty. Doyle ranked "The Adventure of the Empty House" sixth in his list of his twelve favorite Holmes stories.
The story takes place three years after the supposed death of Sherlock Holmes at Reichenbach Falls. The Honorable Ronald Adair, son of the Earl of Maynooth, a high colonial official in Australia, is found murdered. The authorities, not to mention the man's family, are perplexed by the case: it seems that Adair had not an enemy in the world. He was in his sitting room, with a window open, working on accounts of some kind, as indicated by the papers and money found by police. Adair liked playing whist and regularly did so at several clubs, but never for significant sums of money. It does, however, come out that he won as much as £420 in partnership with Colonel Sebastian Moran.
Ronald's door was locked from the inside. The only other way out was the window, and there was a 20-foot (about 6m) drop below it onto a flower bed, which now shows no sign of being disturbed, yet he was killed with a soft-point bullet to the back of his head. No one heard a shot, and the police cannot know where it was fired from.
Dr. Watson, having retained an interest in crime from his adventures with Holmes, visits the crime scene and sees a plainclothes detective there with police, and also runs into an elderly deformed book collector, knocking several of his books to the ground. The encounter ends with the man snarling in anger and going away, but that is not the last that Watson sees of him, for a short time later, the man comes to Watson's study to apologize for his earlier behavior. Once he manages to distract Watson's attention for a few seconds (making Watson turn to his bookshelf to see if there is enough room to fit some books), he shows himself to be Sherlock Holmes, much to Watson's great astonishment. Watson faints, and Holmes helps him up. Watson is overjoyed that Holmes is alive and tells him to explain how he alive. With the help of baritsu, Holmes won against Professor Moriarty, flinging him down the waterfall and then climbing up the cliff beside the path to make it appear as though he, too, had perished. This was a plan that Holmes had just conceived to defend against Moriarty's confederates. However, at least one of them knew that he was still alive and tried to kill him by throwing rocks at him: luckily, Holmes managed to escape and ran for his life.
He then explains that he spent the next three years travelling to various parts of the world. Holmes says that initially, he travelled to Florence. From there, Holmes travelled to Tibet and wandered for two years, even attaining entry to Lhasa. Afterward, Holmes travelled incognito as a Norwegian explorer named Sigerson. Then, he went to Persia and Mecca and then to a brief stopover in Khartoum to meet with the Khalifa. Finally, before returning, Holmes spent time doing chemical research on coal tar derivatives in Montpellier with his brother Mycroft, until finally, Holmes was brought back to England by news of the Adair murder.