The Sign of the Four

Mary Morstan has received a valuable pearl from an unknown sender every year for six years. Now a letter asks her to attend an evening meeting, bring two friends and leave the police out of it. Her father disappeared in London almost ten years earlier, and she takes the puzzle to Sherlock Holmes. For a detective miserable without work, her arrival at Baker Street is welcome; for Dr Watson, the anxious young governess is already much more than an interesting case.

Conan Doyle’s second Holmes novel gives the two companions plenty to disagree about. Holmes complains that Watson has made their previous investigation too romantic in the telling, while Watson finds his friend’s determination to treat people as problems distinctly inhuman. Their exchanges make the detective’s brilliance enjoyable company even when his manners are difficult. Watson admires him, argues with him and notices the feelings that his explanations leave out.

Outside their rooms, London is damp, crowded and hard to read. A cab carries them through fog and unfamiliar streets while Holmes calmly names the turns; Watson, trying to entertain Miss Morstan, becomes so distracted that he muddles his own anecdotes. Such moments give the mystery warmth as well as urgency. This is a compact adventure of close observation, uneasy meetings and sudden movement, told by someone with a personal stake in the people he describes. Follow it for the satisfaction of a difficult puzzle, and for Watson’s struggle to keep his attention on the evidence when his companion insists that nothing else should matter.