After a dreadful summer with the Dursleys Harry Potter can't wait to start his third year at Hogwarts School of Witchcraft and Wizardry.Events take a strange turn however when Harry discovers that Sirius Black the man believed to have betrayed Harry's parents and thus responsible for their murders has escaped from the wizard prison Azkaban. Black appears to be seeking revenge on Harry for thwarting "You-Know-Who while the Dementors Azkaban prison guards sent to Hogwarts to protect the school and recapture Black affect Harry in a disturbing way.With the help of Ron and Hermione Harry is intent on unraveling the mystery surrounding Sirius Black and his escape from Azkaban.