Harry Potter and the Prisoner of Azkaban | Chapter 18 Summary

Chapter Eighteen:  Moony, Wormtail, Padfoot, and Prongs

Black immediately tries to kill the rat, Scabbers/Pettigrew, but Lupin stops him.  Lupin subsequently reveals how the Shrieking Shack is not haunted at all, but was the place where Lupin went to become a werewolf safely.  Lupin was bitten (and consequently began transforming into a werewolf every full moon) as a very young boy. Snape had recently discovered a special potion that would allow Lupin to transform into a “harmless wolf” and to curl up in his office without hurting anyone. While Lupin was still attending Hogwarts as a student, Lupin was told to go through the tunnel to the Shrieking Shack in order to bite and scratch himself (instead of other humans) in order to remain safe at Hogwarts. Lupin’s friends, instead of deserting their poor friend, decided to become Animagi themselves and keep Lupin company while he was a werewolf. Finally, the mystery behind the “manufacturers” of the map are revealed. Lupin is Mooney, for he is a werewolf brought about by the full moon.  Wormtail is Peter Pettigrew who can change himself into a long-tailed rat. Padfoot is Sirius Black who is also an animagus, able to change himself into a large black dog. Prongs is James Potter (Harry’s Dad), who was the last of the Animagi, able to turn himself into a large stag with enormous antlers. Lupin finally reveals exactly how James Potter saved Snapes life.  When all of them were attending Hogwarts, Snape was very interested in where the four friends went every month at the full moon. Sirius let it “slip” once about how to enter the tunnel beneath the Whomping Willow. When Snape followed, James Potter pulls him back in order to save his life.  At the end of the tunnel, Snape caught a glimpse of Lupin as a fully-grown werewolf. Suddenly, Snape (who had found the invisibility cloak left at the base of the Whomping Willow by Harry), appears and points his wand directly at Lupin.