Harry Potter and the Prisoner of Azkaban is a fantasy novel written by British author J. K. Rowling and is the third in the Harry Potter series. The book follows Harry Potter, a young wizard, in his third year at Hogwarts School of Witchcraft and Wizardry. Along with friends Ronald Weasley and Hermione Granger, Harry investigates Sirius Black, an escaped prisoner from Azkaban, the wizard prison, believed to be one of Lord Voldemort's old allies.

Joanne Rowling ; born 31 July 1965), known by her pen name J. K. Rowling, is a British author and philanthropist. She wrote Harry Potter, a seven-volume fantasy series published from 1997 to 2007. The series has sold over 600 million copies, been translated into 84 languages, and spawned a global media franchise including films and video games. The Casual Vacancy (2012) was her first novel for adults. She writes Cormoran Strike, an ongoing crime fiction series, under the alias Robert Galbraith.