After a pupil at the prestigious Devington School dies of a stab wound suffered while competing in a race, shocked locals are sure the death can be linked to the long-running rivalry between the school and the locals. As Barnaby investigates, he encounters the Pudding Club, an elite secret society with which the murdered student had been involved. After a local Devington man is found murdered on the school grounds, Barnaby finds that one man is willing to kill to keep the morbid history of the Pudding Club from being exposed.