Prof. Abditus Questor
Book 3: Harry Potter and the Prisoner of Azkaban
PLOT SUMMARY: Harry runs away from Privet Drive, because Vernon Dursley’s sister, Aunt Marge, comes for a visit and insults Harry’s parents, provoking Harry unconsciously to swell her up like a balloon, so that she is physically as well as metaphorically full of hot air. On the street, Harry thinks he is watched by a large black dog (see below on Sirius Black's name), but he reaches the Leaky Cauldron, where he stays until leaving for Hogwarts. The Hogwarts Express is boarded by Dementors looking for Sirius Black, who has escaped from the prison of Azkaban (cf. Alcatraz), where he was sent for supposedly betraying Harry's parents to Voldemort. The Dementors radiate fear and despair, and they cause Harry to become unconscious. At Hogwarts, the new Defence against the Dark Arts professor is Remus Lupin, the best they have ever had; he teaches Harry a Patronus Charm to repel the Dementors. He was one of four fellow students at Hogwarts with Harry's father, but he is a werewolf, having been bitten by one when he was a small boy, so James Potter, Sirius Black, and Peter Pettigrew became animagi (wizards who can transform themselves into animals)—assuming the forms of a stag, dog, and rat, respectively—to accompany Lupin when the full moon turned him into a wolf. Pettigrew betrayed the Potters but put the blame on Sirius; and in his rat form, he went into hiding, masquerading as a familiar animal of the Weasley family and eventually becoming Ron's pet. Hagrid now teaches Care of Magical Creatures and brings to class a hippogriff (a proud creature that is half horse, half eagle) named Buckbeak, which Harry befriends, but which mauls Draco Malfoy for insulting him. Consequently, Buckbeak is condemned to be destroyed. But Hermione has been using a Time-Turner, which allows her to go back in time to take several classes at once, so she and Harry use it to free Buckbeak from execution and arrange for the hippogriff to fly Sirius to a hiding place, where he is safe from the Dementors and Azkaban.
Harry's specific quest in this book is to save Sirius, who was James Potter's best friend and is Harry’s godfather. Harry achieves this quest by using the Patronus Charm and by establishing harmony with the hippogriff Buckbeak. The Patronus [Latin for “protector, defender, patron”] is a silvery form projected by a wizard and embodying hope, happiness, and wellbeing to counteract the effects of Dementors, who drain all joy and happiness from others. (Dementia is "mental deterioration and emotional apathy" with no known cure; it includes Alzheimer's and has been called "the greatest medical challenge of the 21st Century.") The Dementors are faceless beings, having only a mouth with which they suck the soul, sense of self, and memory out of their victims, leaving them as the living dead. Harry at first has great difficulty with this very advanced charm, but finally, when he himself is attacked by Dementors, sees a familiar-looking figure in the distance working it perfectly to scatter the threatening Dementors. At first he thinks the figure is his father. But later he realizes the figure was actually himself when he had used the Time-Turner to come back to save Buckbeak and Sirius. As a result, he can use the charm consciously and effectively, having discovered his own positive force.
A major theme of this book is Harry's need for a father to serve as his guide and model. That theme echoes throughout the entire series. Harry is very much like James Potter, his biological father, in his ungoverned hair, slim physique, somewhat unruly behavior, and Quidditch ability; Prof. Snape calls the resemblance between father and son "uncanny." Only Harry's eyes (which are the windows of the soul) are like his mother's. Harry also inherits from James several objects that serve him well: a cloak of invisibility and the Marauder's Map. James had been killed by Voldemort when Harry was one-year old, just before the start of the first book. In that book, Harry is longing for a family, so he sees himself with his father and mother in the Mirror of Erised ("desire" spelled backward). The mirror has an inscription, also in backward writing, for "I show not your face but your heart's desire." So Harry's heart's desire is to be with his parents. In the third book, Aunt Marge's insults of Harry’s father and mother cause him to make her inflate like a balloon. Harry's early loathing of Sirius Black is due to his belief that Sirius had betrayed his father and mother to Voldemort. When Harry learns the Patronus charm, the patronus he evokes has the shape of a stag, which was the animal form his father (nicknamed "Prongs") assumed as an animagus. Although Harry never knew his father personally, James is a strong force in Harry's life, and Harry idolizes him.
In addition to James, Harry has three other father figures (defined by Merriam Webster as "a person often of particular power or influence who serves as an emotional substitute for a father"). One is Sirius Black, who first appears in book three. Sirius was James's best friend and is Harry's godfather. Through much of the book, Harry fears and hates Sirius who he thinks betrayed his parents and is trying to kill him. However, after Harry learns that Sirius was framed by Peter Pettigrew for the latter's crimes but was always loyal to James and concerned for Harry's welfare, Harry forms an intense attachment to him. He looks forward to living with Sirius during school holidays and joining with him in a family relationship unlike any he has known before. Sirius's name is that of the brightest star in the heavens, part of the constellation Canis Major ("greater dog"), also called the "Dog Star." His animagus form is a big black dog (nicknamed "Padfoot"); that and his name bespeak his honesty and loyalty. Thereafter, he plays a major role in Harry's life as protector and guide.