Visiting her aunt in Winchester, Cressida Fawcett discovers the murdered body of Anthony, the verger, in the cathedral’s crypt, with her aunt’s maid, Nancy, standing over him. Despite Nancy’s plea of innocence and Detective Andrews’ quick judgment, Cressida believes there’s more to the story. Investigating Anthony’s enemies and uncovering cathedral secrets, she finds a hidden passageway, suggesting a different escape route for the murderer. Cressida races against time to prove Nancy’s innocence and solve the murder, facing skepticism from the police.