Two Sherlock Holmes stories use third-person narration rather than Watson's first-person perspective: 'The Adventure of the Mazarin Stone' and 'His Last Bow'. 'His Last Bow' (1917) is subtitled 'The War Service of Sherlock Holmes' and uses third-person to depict Holmes in an espionage context during World War I. 'The Adventure of the Mazarin Stone' was adapted from a one-act play. Most canonical stories, including 'The Boscombe Valley Mystery', are first-person Watson narratives.