Charters and Caldicott are now settled comfortably into retirement when their leisurely routine of lunch at the Club and amiable argument about cricket averages from days long past is shattered when the body of a strange girl is found in Caldicott's flat. Dogged by the fastidious and disapproving Inspector Snow, they attempt to unravel the mysteries around them: switched handbags, unexplained deaths, cryptic messages, such as "Mix Well and Serve," and a fellow clubman who…