The Murders of Richard III (Jacqueline Kirby Series #2)

Second book in the Jacqueline Kirby series. Jacqueline Kirby is invited to an English country mansion for a weekend costume affair. The hosts and guests, all fanatic devotees of King Richard III, hope to clear his name of the five- hundred-year-old accusation of murder. Jacqueline is amused at first at the group's eccentricities, until the antics of a practical joker become more and more macabre, and one at last proves fatal.