The plot starts when Sirius Black, a convicted mass murderer, escapes Azkaban prison and may be after Harry. As a precaution, Harry's government enlists the help of dark forbidding creatures known as dementors to guard the school. The dementors watch the Hogwarts' grounds ready to attack Sirius Black if he attempts to enter. But the dementors may not hold to just attacking Black. Whenever a dementor draws near, a person is filled with haunting memories and despair so great that they believe they can never be happy again. With the ever present threat of Sirius Black dwelling in the background, Harry must live in a darker world than he has ever known, facing dementors at every turn and being continuously stalked by his own grief and fear.
The story that J.K. Rowling presents to her readers in this third volume is brilliant. She touches on a number of compelling themes. For instance, the death penalty and its place in society is a constant conversation throughout the book. Sirius Black, if caught, is to be given the death penalty by the dementors that will suck out the criminal's soul. This parallels another storyline in which a magical creature attacks a student and is sentenced to death for the crime. Should Buckbeak, the magical creature, die just because a human taunted him into attacking? Does a villain as dark as Sirius Black deserve a punishment worse than death? Rowling stands her ground with a firm no as played out in the different characters' actions.
Lupin also gives Harry some private lessons on how to fight the dementors. Keeping with the same theme of fighting fear with laughter, Lupin teaches Harry to fight despair with happiness. The only way to stop a dementor is to think of the happiest thought you can conceive and then let it fill your entire being.
Harry Potter and the Prisoner of Azkaban is probably the first book of the series that will truly appeal to an adult's intellect. No longer locked up in just a fantasy world, this new book explores the depths of emotions that haunt and enchant all mankind.
Adult readers will also appreciate the plethora of themes throughout the novel. Besides emotional and political themes, Rowling explores the preciousness of time, the unpredictability of the future, and the bonds of lasting friendship and courage.
The characters are well developed, the mystery is hard to guess, and the themes are honest. An excellent book with a page-turning plot, Harry Potter and the Prisoner of Azkaban earns four stars and a standing ovation.