During her final year at Hogwarts, which is a year after the defeat of the Dark Lord, Isla Riddle is disturbed by a series of events that target her, bearing the name of You-Know-Who. She becomes suspicious with the arrival of a new headmistress who, by chance, bears the name of the founder of Slytherin. Additionally, Lorenzo Berkshire, a Death Eater but also the brightest student at Hogwarts, receives an invitation to become a teacher at the magical school, making him the youngest professor in the entire school.