Author : J.K.Rowling
Harry's third year in Hogwarts is the theme of third book in the Harry Potter series. The readers expected another encounter with 'you know who' but this time Harry has another battle in hand.
The story begins when Sirius Black, a convicted mass murderer escapes Azkaban prison and the speculation is rife that he may be after Harry. Dementors are called out to guard Hogwarts but when Dementors come very close to an individual, they tend to suck out all the happiness out of that individual. But their services are mandatory in this uncertain time so Harry has to face his grief, fear and all disturbing memories and emotions. He eventually learns the secret of Sirius Black, his relation with his parents and about the actual killer.
Introduction of Lupin as teacher of Defense Against the Dark Arts is a great addition to the series. He effectively teaches the students to tap their inner strength and energies in order to fight against the evil and despair. No one is devoid of happy or hopeful feelings. 'Harry Potter and the Prisoner of Azkaban' is primarily devoted to emotions and feelings and learning the capability to steer them favourably.
I really liked the way author brings out the angst and inner turmoil of Harry and how eventually his positivity triumphs over all negativity. It is so true in general too, no matter how difficult the impediments are, they just need to be combated with more positive energy and thoughts.