American librarian Jacqueline Kirby is invited to an English country mansion for a weekend of role-playing and scholarship centered on King Richard III. Jacqueline is amused at the groups eccentricities--until history begins to repeat itself. A dangerous practical joker begins recreating famous fifteenth-century murder methods--beheading, poisoning, smothering, and even drowning in a butt of malmsey. As the jokes become more and more macabre, one at last proves fatal.