A year after the final battle, Hogwarts resumes. Among the returning are Draco, Blaise, and Theo. Theo's new girlfriend Daphne, who is not returning, asks him to keep an eye out for her sister to make sure she doesn't get in any trouble. Theo enlists the help of his friends for this task. However, Draco Malfoy has no intention of spending the year babysitting Astoria Greengrass.