A ship's crew encounters a derelict brig in the Atlantic, which appears abandoned and damaged. The captain and his second mate, Allardyce, decide to investigate. They discover the brig's name, _Nossa Sehnora da Vittoria_, and its Brazilian flag flying upside down, indicating distress. Upon boarding, they find the vessel littered with wreckage and a dead crew member, murdered with a blow to the head. The captain learns of a treasure chest belonging to Don Ramirez di Leyra, which is heavily locked and marked with warnings not to open it. Despite the warnings, the crew's curiosity grows, especially that of the first officer, Armstrong, who is eager to open the chest. The captain, however, insists on leaving it closed. Later that night, Armstrong is found dead in the cabin, having attempted to open the chest. The captain and Allardyce suspect foul play and theorize that a man may be hiding inside the chest, leading to the deaths of both the sailor and Armstrong. Determined to uncover the truth, the captain and Allardyce prepare to open the chest. They are joined by the carpenter, and as they unlock it, they discover a hidden mechanism that causes the lid to snap shut violently, revealing the chest's deadly secret: it is rigged to kill anyone who attempts to take its contents. Realizing the danger, the captain orders the chest to be thrown overboard, ensuring that its dark history and the potential for further violence are buried in the depths of the ocean. The story concludes with the chest sinking, leaving its mysteries and the fate of its previous victims to the sea.
By Sir Arthur Conan Doyle · First published 1892 · Genre: Mystery, Adventure, Thriller