Sherlock Holmes and Dr. Watson are visited by "the unhappy John Hector McFarlane", a young lawyer who has been accused of murdering one of his clients, a builder called Jonas Oldacre. McFarlane explains to Holmes that Oldacre had come to his office only the day before and asked him to draw up his will in legal language. McFarlane saw to his surprise that Oldacre was making him the sole beneficiary, and heir to a considerable bequest at that. McFarlane could not imagine why.
