Sirius Black

Sirius Black is a fictional character in the Harry Potter series of novels by J. K. Rowling. Sirius was first mentioned briefly in Harry Potter and the Philosopher's Stone as a wizard who lent Rubeus Hagrid a flying motorbike shortly after Lord Voldemort killed James and Lily Potter. His character becomes prominent in Harry Potter and the Prisoner of Azkaban, in which he is the titular prisoner, and is also revealed to be the godfather of the central character Harry Potter. He is portrayed in the film adaptations by Gary Oldman.

Sirius Black is the last heir of the House of Black, a once notable Pure-blood Wizarding family. His parents, Orion and Walburga Black, were both Blacks by birth and second cousins. Sirius had a younger brother, Regulus Arcturus Black, and three older cousins: Bellatrix Lestrange, Andromeda Tonks (his favourite cousin and mother of Nymphadora Tonks), and Narcissa Malfoy (mother of Draco Malfoy). In line with the Black family tradition of naming children after stars and constellations, Sirius was named after the Dog Star. Sirius's early life proved unhappy; he had come to hate most of his relatives, in particular his mother. He rejected his family's pure-blood elitism and reverence for the Dark Arts. At Hogwarts, rather than be sorted into Slytherin like the rest of his family, Sirius was placed in Gryffindor.

In contrast to his home life, Sirius greatly enjoyed life at Hogwarts, where he was inseparable from his best friend, James Potter. Sirius and James were immensely popular and known for their exceptionally good looks. Students liked his biting humour, and teachers respected his intelligence, though not his behaviour. His popularity was not universal, as a mutual hatred sprang up between James and Severus Snape. Sirius actively supported James, leading to Snape developing an equal and lifelong loathing of Sirius. Sirius and James often went out of their way to bully Snape, whom they despised for his great interest in the Dark Arts. They also became best friends with Peter Pettigrew and Remus Lupin, whom they later discovered was a werewolf. To support Remus, Sirius, James, and Peter secretly became Animagi, which allowed them to safely accompany Remus during his transformations and keep him under control. Sirius's form is that of a huge black dog, from which his nickname Padfoot was derived.

Sirius ran away from home at the age of sixteen and took refuge with James and his parents. His outraged mother burned his name off the family tree. Sirius' Uncle Alphard left him a large inheritance, causing Sirius' mother to also remove Alphard's name. He was left financially independent by his uncle's generous bequest. After leaving school, Sirius fought against Voldemort, eventually joining the Order of the Phoenix. He remained close friends with James and eventually attended James and Lily Evans' (now Lily Potter) wedding as their best man. When their son, Harry, was born, Lily and James named Sirius as Harry's godfather.

When the Potters became aware that Harry was Voldemort's specific target, Albus Dumbledore advised them to go into hiding using the Fidelius Charm, a highly complex spell allowing a secret to be concealed within another person. Trusting Sirius above all of their other friends, Lily and James wanted him to be their Secret Keeper. Sirius, however, worried that Voldemort would immediately suspect him of being the Potters' Secret Keeper and would target him; so he convinced the Potters to reassign Pettigrew as their Secret Keeper because he did not believe Voldemort would ever suspect a "weak, talentless thing" like Pettigrew. As it turned out, Pettigrew was Voldemort's spy within the Order. He betrayed the Potters to Voldemort, who subsequently tracked them down and murdered them.

After giving his motorbike to Hagrid so that Hagrid could deliver Harry to the Dursleys, Sirius then tracked down Pettigrew, determined to kill him in revenge. However, Pettigrew outwitted him: confronted by Sirius on a city street, he created an explosion, faking his own death (leaving a severed finger behind as evidence) and killing twelve Muggles in the process. Sirius was arrested, accused of murdering Pettigrew and the muggles and of serving Voldemort, and was promptly thrown in prison by Barty Crouch, Sr. without receiving a trial. He spent the next twelve years in Azkaban, brooding over his friends' deaths and obsessing over Pettigrew's betrayal. Sirius states that unlike most other Azkaban prisoners (who often became insane during their terms of imprisonment), he was able to keep his sanity because he knew he was innocent, and also used his Animagus form to ward off the Dementors, who are unable to perceive unsophisticated canine minds.

Twelve years into his sentence, Sirius sees a picture of the Weasley family on the front cover of the Daily Prophet. He notices the pet rat Scabbers perched on Ron Weasley's shoulder. This serves as a turning point in the series and sets the events of the third novel, as Sirius immediately recognises Scabbers as Pettigrew's Animagus form. He realises that stationed at Hogwarts, Pettigrew will easily be able to deliver Harry to Voldemort should Voldemort ever regain power. This knowledge clears his mind and gives him the mental strength to escape Azkaban. He is the first person known to have escaped the wizard prison by his own means, accomplishing this feat by transforming into his Animagus dog form. The dementors' inability to detect Animagi, along with his severe weight loss from malnutrition, allow him to slip through his cell bars. After his escape, Sirius takes refuge in and around Hogsmeade, intent on exacting revenge upon Pettigrew and remaining near Harry. Knowing that the dementors have been stationed around Hogsmeade and at Hogwarts, Sirius remains in his Animagus form during this time, and is able to enter the Hogwarts grounds without being recognised by the dementors. Harry catches several glimpses of Sirius in his dog form and mistakenly believes him to be the Grim. He befriends Hermione Granger's cat Crookshanks, who is aware that Sirius is not actually a dog and who recognises Pettigrew for what he really is. Sirius breaks into Gryffindor tower at one point with a knife looking for Pettigrew, having had Crookshanks obtain Neville Longbottom's list of the dorm passwords, and shreds Ron's curtains after finding Pettigrew gone, due to Pettigrew having faked his death and framed Crookshanks. After Harry's broom is destroyed by the Whomping Willow during a Quidditch match invaded by Dementors, Sirius anonymously sends Harry a Firebolt as a Christmas gift, although it is confiscated by Professor McGonagall on suspicion that the broom is jinxed.

Towards the end of the novel, Harry, Ron, and Hermione confront Sirius and Harry nearly kills him; however, Lupin's timely intervention stops Harry. Lupin, who has learned that Sirius is innocent, is reunited in friendship with him. Pettigrew is unmasked, and, most importantly, Harry stops Sirius and Lupin from murdering Pettigrew, arguing that his father would not want his friends to commit murder. Harry begins to view Sirius as a surrogate father, although events swiftly turn against him again – Pettigrew escapes, and Sirius is captured by the dementors at Hogwarts and sentenced to the Dementor's Kiss, a fate worse than death. Harry and Hermione help him escape with Buckbeak, a hippogriff who had also been unjustly condemned. Sirius is once again a wanted man.