Returning for his fifth year of study at Hogwarts, Harry is stunned to find that his warnings about the return of Lord Voldemort have been ignored. Left with no choice, Harry takes matters into his own hands, training a small group of students to defend themselves against the dark arts.

Year three at Hogwarts means new fun and challenges as Harry learns the delicate art of approaching a Hippogriff, transforming shape-shifting Boggarts into hilarity and even turning back time. But the term also brings danger: soul-sucking Dementors hover over the school, an ally of the accursed He-Who-Cannot-Be-Named lurks within the castle walls, and fearsome wizard Sirius Black escapes Azkaban. And Harry will confront them all.