Harry Potter is owned by JK Rowling
Chapter 4: Prisoner of Azkaban
"speech"
(thoughts)
thoughts
thoughts
thoughts
Parseltongue
The big news at the beginning of the summer was that Peter Pettigrew had escaped from Azkaban. As a result, Dementors were stationed at Hogwarts and Remus Lupin was hired to teach Defense Against the Dark Arts. Harry knew Professor Lupin well, as he had seen him often over the past two summers when visiting his godfather, Sirius Black.
Because Harry knew him well, the existence of the D.A. was revealed to Lupin, and he agreed to teach its' members extra lessons that were beyond their level.
The presence of the Dementors gave Harry incentive to learn the Patronus Charm and Luna pretended to pick it up just as easily.
At the end of the year, since Pettigrew had not been seen at Hogwarts, the Dementors were withdrawn.