'The Adventure of the Naval Treaty', one of Sir Arthur Conan Doyle's 56 Sherlock Holmes short stories, is included in the collection The Memoirs of Sherlock Holmes. First published in The Strand Magazine in the UK (October–November 1893) and Harper's Weekly in the US (October 1893), the story features Holmes investigating the mysterious disappearance of an important Foreign Office document. The case begins when Percy Phelps, a young government clerk, seeks Holmes's help after suffering a debilitating illness linked to the loss.