Chapter 18 Summary

Harry, Ron and Hermione do not believe them at first. They just find the whole idea absurd. Black lunges for Scabbers/Peter, anxious to kill him. He is in as much a rage at Peter as Harry was at him. Lupin tries to stop him, telling him they must explain what is going on. He pulls Black away from Ron, who is still clutching Scabbers tightly in his grip. Black agrees to let Lupin explain, but to be quick about it.

Professor Lupin explains to the three that as a young child, he was bitten by a werewolf. In order to attend Hogwart's, the Womping Willow and the Shrieking Shack were put in place for him to transform without hurting anyone. People thought the Shack was haunted, because they would hear his howling and screams, as he transformed every full moon.

Lupin's best...