Harry Potter and the Prisoner of Azkaban

Harry Potter and the Prisoner of Azkaban by J.K. Rowling, 1999 Bloomsbury

     After nearly being killed by a book, Harry Potter is seeing strange shapes in the shadows. First a cloaked figure then a large, shaggy dog, but things are getting out of hand when one of the strangely cloaked figures attacks him while Harry and his cousin, Dudley, are in a public playground. Harry is sent an owl from the Ministry of Magic and scolded for his use of magic in front of a Muggle.
     When Aunt Marge comes to visit she, like the rest of her family, demeans Harry's parents and Harry himself. In a fit of rage Harry unwittingly uses magic to inflate her like a helium balloon and escapes in the aftermath. He is picked up by the Knight Bus and travels to Diagon Alley where he runs into the Minister of Magic himself. Fudge asks Harry to spend the rest of his summer in Diagon Alley where he may be protected and looked after.
     As he takes the train back to Hogwarts with Ron and Hermione, Harry discovers that Fudge wanted him accounted for because Sirius Black, Harry's Godfather and a convicted murderer has escaped from Azkaban Prison. Nearly everyone assumes Black plans to murder Harry and the Ministry has sent Dementors to patrol the school and surrounding areas.
     The Dementors are soul-sucking hooded creatures capable of stealing an individual's happiness and making them relive their worst memories. When one appears on the train, the new Defense Against the Dark Arts' Professor Lupin defends the trio and helps them recover with chocolate. It is not the first or last time Harry encounters the Dementors: he falls nearly fifty feet during a Quidditch match when a group swarms him. The problems urge Harry to take lessons from Lupin on a patronus charm, which repels the creatures.
     Third Years are offered the opportunity to visit the nearby town of Hogsmeade, but when Harry doesn't have permission from his guardian he is confined to the grounds. Fred and George Weasley, however, have other plans and deliver into Harry's possession the Maurader's Map. The Map was created by Mooney, Wormtail, Padfoot, and Prongs in years gone by and shows the location of any person within Hogwarts grounds, as well as passages off campus. Harry uses the map and his father's invisibility cloak to sneak into Hogsmeade where he meets up with Ron and Hermione. On one such trip Harry overhears several professors speaking about Black: how he betrayed Harry's parents, his true relationship to Harry, how he murdered not only muggles but friend Peter Pettigrew, and how he is thought to be working for Voldemort.
     The boys' relationship with Hermione is strained when she reports Harry's Christmas gift of a state-of-the-art broomstick (to replace his Nimbus 2000 after it was destroyed by the Whomping Willow), and only made worse when Ron thinks her cat ate his rat. But when Hagrid needs their support, the friends reconcile to be there for him as Buckbeak the Hippogriff is executed for attacking Malfoy (but not without reason).
     Harry, Ron, and Hermione go to the gamekeeper's cottage where they hear the axe of Buckbeak's execution. As they prepare to leave Ron's rat flees and Ron chases after him, only to be dragged down a tunnel beneath the Whomping Willow by a large black dog that has been following Harry about.
     Hermione and Harry follow where they discover Sirius Black with Ron. Lupin interrupts their standoff to explain the situation. Lupin is a werewolf and his friends became animagi, wizards who could transform into a chosen animal, so they might spend time with their friend. James Potter became a stag, Sirius Black became a large black dog, and Peter Pettigrew transformed into a rat. That rat became Scabbers, Ron's pet. Old feuds break out among the three remaining friends and Pettigrew escapes. Harry, Ron and Hermione must hurry to make it back to the castle as Lupin transforms into his were-self and Sirius chases him away from the children. They run into several Dementors and wake in the hospital wing.
     Dumbledore explains that Black is awaiting the Dementor's Kiss, which sucks the soul out of a person's body, and Harry and Hermione must go back with Hermione's Time Turner to save the day. They manage to save Buckbeak and themselves and arrive back in their hospital wing beds when Dumbledore returns with the news that Black has escaped.
     The trio's third year at Hogwarts is full of caution and the results of misrepresented facts. Though Black was not the one to betray the Potters, he feels guilty for being unable to stop them. The guilt has sentenced him to twelve years in the wizarding world's high security prison, a punishment beyond his perceived crimes. Yet when the truth is revealed, he relieves himself of that guilt to become the man James Potter made godfather to his only son. Without Harry's search for the truth and Sirius' insistence he must repay the debt to his only remaining family, Sirius Black might have continued to live in a self-imposed prison.
     This story illustrates the power of forgiveness and how strongly guilt can hold a person in thrall. It is aimed at young adults from middle school age through adulthood. Though some concepts of time travel can be difficult for young readers to understand, the ideas behind them and that the travel supports are simple and easily explained.