For twelve long years, the dread fortress of Azkaban held an infamous prisoner named Sirius Black. Convicted of killing thirteen people with a single curse, he was said to be the heir apparent to the Dark Lord, Voldemort. Now he has escaped, leaving only two clues as to where he might be headed: Harry Potter’s defeat of You-Know-Who was Black’s downfall as well. And the Azkaban guards heard Black muttering in his sleep, “He’s at Hogwarts...he’s at Hogwarts.”
Harry Potter isn’t safe, not even within the walls of his magical school, surrounded by his friends. Because on top of it all, there may well be a traitor in their midst.
Harry Potter's third year at Hogwarts is full of new dangers. A convicted murderer, Sirius Black, has broken out of Azkaban prison, and it seems he's after Harry. Now Hogwarts is being patrolled by the dementors, the Azkaban guards who are hunting Sirius. But Harry can't imagine that Sirius or, for that matter, the evil Lord Voldemort could be more frightening than the dementors themselves, who have the terrible power to fill anyone they come across with aching loneliness and despair. Meanwhile, life continues as usual at Hogwarts. A top-of-the-line broom takes Harry's success at Quidditch, the sport of the Wizarding world, to new heights.
A cute fourth-year student catches his eye. And he becomes close with the new Defense of the Dark Arts teacher, who was a childhood friend of his father. Yet despite the relative safety of life at Hogwarts and the best efforts of the dementors, the threat of Sirius Black grows ever closer. But if Harry has learned anything from his education in wizardry, it is that things are often not what they seem. Tragic revelations, heartwarming surprises, and high-stakes magical adventures await the boy wizard in this funny and poignant third installment of the beloved series.