在这部圣玛丽节命案剧情/悬疑/犯罪片中,
The Devington school has a long history of educating the privileged members of society and many have gone on to illustrious careers, such as in the Diplomatic Service. The Talbot family in particular has a long association with the school with three generations having attended. When Daniel Talbot is killed during the St. Malley's Day race, the same day his elderly grandfather dies of natural causes, Barnaby and Troy investigate. They find ongoing feuds between the school and villagers, a conspiracy theorist who thinks the school is the center of criminal activity, students who are having drinking parties at the local pub and the ongoing affairs of the school's secretive Pudding Club. The discovery of a long-held school secret leads to the discovery of the murderer.