Harry Potter and the Prisoner of Azkaban (2004)

During a summer with the Dursleys, Harry Potter loses his temper and inadvertently causes Aunt Marge to inflate like a balloon and float away. Fed up, Harry flees the Dursleys with his belongings. The Knight Bus arrives and takes Harry to the Leaky Cauldron, where he is pardoned by Minister for Magic Cornelius Fudge for using magic outside of Hogwarts. After reuniting with his best friends Ron Weasley and Hermione Granger, Harry learns that Sirius Black, a convicted supporter of the dark wizard Lord Voldemort, has escaped Azkaban prison and intends to kill him.

Harry, Ron, and Hermione return to Hogwarts for the school year on the Hogwarts Express train, which is suddenly boarded by dementors, ghostly prison guards that are searching for Black. One enters the trio’s compartment, causing Harry to pass out, but new Defence Against the Dark Arts teacher Remus Lupin repels the dementor with a Patronus Charm. At Hogwarts, headmaster Albus Dumbledore announces that dementors will be guarding the school until Black is captured. Hogwarts groundskeeper Rubeus Hagrid is announced as the new Care of Magical Creatures teacher; his first class goes badly when Draco Malfoy deliberately provokes the hippogriff Buckbeak into attacking him. Draco exaggerates his injury, and his father Lucius Malfoy has Buckbeak sentenced to death.