"The Rhesus Chart" is a novel by Charles Stross that combines elements of science fiction and fantasy. It follows the story of Bob Howard, a member of a secret organization called the Laundry, which deals with supernatural threats. The plot revolves around a mysterious chart that connects to a dangerous conspiracy involving vampires and ancient powers. In this book, Stross explores themes of bureaucracy, technology, and the supernatural. The narrative is filled with humor and clever twists, making it an engaging read for fans of urban fantasy. The characters navigate a world where magic and mathematics intersect, leading to unexpected challenges.