Charles was once described by The Guardian as a "a blood stained version of Barbara Pym". Though an American, she has a firm grasp of both British English and the nuances of British society. Her series of clerical mysteries is set against the contemporary Church of England, with plots often inspired by real-life controversies in the church. A Dead Man Out of Mind, for example, explores the controversy surrounding women priests, while Appointed to Die shows how an abrasive new dean can turn a placid cathedral close into an arena for vicious ecclesiastical infighting. Charles’s protagonists and plots tend to be less interesting than her clerical characters and her skilfully observed settings.