Harry Potter is at the Dursleys’ for the summer, spending his time studying new spells undercover. When Uncle Vernon’s sister, Marge, comes for a visit and infuriates Harry by insulting his parents, he accidentally causes her to inflate and fly away. Harry loses his temper and threatens to curse Vernon but flees, fed up with his life at Privet Drive. The Knight Bus appears and delivers Harry to the Leaky Cauldron, where Minister of Magic Cornelius Fudge tells him he will not be arrested. Harry also learns that Sirius Black, a convicted supporter of Lord Voldemort, has escaped Azkaban prison and is likely intending to kill Harry.
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Tags: Harry Potter, Prisoner of Azkaban