Ron chases Scabbers, only to be attacked by a big black dog who drags him through a tunnel under the Whomping Willow into the Shrieking Shack. Their efforts are unsuccessful, but Scabbers reappears shortly after Buckbeak is executed. Harry, Ron, and Hermione try to save Hagrid’s hippogriff Buckbeak from execution after it attacks Draco Malfoy.

Fearing that it might be cursed, Hermione reports it to McGonagall. At Christmas, Harry receives a state-of-the-art Firebolt broom as a gift, but there is no card or indication of who sent it. Ron and Hermione’s friendship suffers because Ron believes that Hermione’s cat, Crookshanks, ate his rat, Scabbers. Black was also convicted for killing thirteen Muggles and their friend Peter Pettigrew. Harry uses the map to sneak to Hogsmeade where he overhears a conversation among faculty members about how Sirius Black was a family friend and godfather to Harry, who betrayed his parents and provided Voldemort with the location of their safehouse. George and Fred Weasley give Harry a Marauder’s Map, which details hidden passages in Hogwarts and live markers of the people who travel them. Without a permission slip signed by a guardian, Harry is unable to participate in weekend excursions to Hogsmeade with the rest of the upperclassmen. Lupin, outside of class, teaches Harry to repel Dementors using the Patronus Charm. His broom is smashed by the Whomping Willow. Harry has several problems with the Dementors, including an event where during a quidditch match, he faints and falls off his broomstick 50 feet in the air. Harry, Ron, and Hermione learn that the Dementors will be patrolling around the school in order to protect Harry from Sirius. Luckily, the new Defence Against the Dark Arts teacher Remus Lupin is there to fend it off. The next day, a Dementor boards the Hogwarts Express, causing Harry to faint. The night before the Hogwarts Express departs, Harry learns that Sirius Black is a convicted murderer, who is believed to want to murder Harry. Fudge tells Harry that he has to stay in Diagon Alley for the remaining three weeks before school starts again. He travels to Diagon Alley where he meets Cornelius Fudge, the Minister of Magic. Just as he's realizing he has no way to connect with anyone in the wizarding world, he's picked up by the Knight Bus, an emergency travel service for stranded witches and wizards. This forces him to pack his bags and leave the house.

During Vernon’s sister Marge’s visit to Privet Drive, Harry accidentally inflates her after she makes rude comments about his parents. Harry is back with the Dursleys, where he sees on the Muggle news that a prisoner named Sirius Black has escaped.

Harry potter azkaban