Chương 17 trong phần truyện Harry Potter và Tên Tù Nhân Ngục Azkaban có tên: Cat, Rat and Dog
Still hiding under the Invisibility Cloak, Harry, Ron, and Hermione debate whether to return to comfort Hagrid, eventually deciding to proceed to the castle. Scabbers bites Ron, who struggles to hold him. Harry spots Crookshanks approaching, apparently homing in on Scabbers' squeaks. Scabbers escapes, with Crookshanks in hot pursuit. Ron goes after Scabbers, and Harry and Hermione fling off the Cloak and chase after him. Ron catches Scabbers, but a large black dog appears, knocking Harry aside and grabbing Ron. The dog drags Ron into a hole under the roots of the Whomping Willow, breaking Ron's leg. Harry, trying to follow, is struck by one of the Willow's flailing branches.
Crookshanks dives under the branches and presses a knot in the tree trunk. The branches fall still; following Ron and the black dog, Harry and Hermione enter a tunnel that leads to the Shrieking Shack. Upstairs, Ron, lying beside a decrepit four-poster bed, warns them it is a trap; the dog is Sirius Black, an Animagus. Black disarms Harry and Hermione with Ron's wand.
Sirius remarks he is glad Harry acted like his father, coming to save his friend rather than running for help; that makes things easier. Ron says Black will have to kill them all, not just Harry, but Black responds there will only be one murder tonight. Harry demands to know if killing twelve Muggles plus Peter Pettigrew were not enough and lunges at the visibly weakened Black, grabbing his wand wrist. Black chokes Harry with his free hand. Hermione kicks Black while Ron grabs his wand hand. Despite Crookshanks clawing at his hand, Harry recovers his wand, which is rolling free, while Hermione grabs her own wand and Ron's. Defenseless, Black asks if Harry is going to kill him. Harry says he knows Black betrayed his parents to Voldemort. Black admits he was responsible but there is more to the story. As Harry decides whether or not to listen, Crookshanks deliberately sits on Black's chest, resisting Black's efforts to remove him.
Professor Lupin suddenly bursts in, disarms Harry, Ron, and Hermione, and asks, "Where is he?" Black points at Ron. Lupin demands, "Why hasn't he shown himself? Unless... you switched... and didn't tell me?" Black nods. Lupin pulls Black to his feet, embracing him. Hermione, sounding betrayed, tells Lupin that she trusted him and protected his secret that he is a Werewolf. Lupin admits that he is a Werewolf, but he has not been helping Black, nor does he want Harry dead. The Hogwarts staff knows he is a Werewolf; Professor Dumbledore convinced them he was trustworthy. Professor Snape set the Werewolf assignment with the expectation that a student would detect Lupin and give away his secret.
Lupin returns the Trio's wands, placing his own wand in his belt, and asks the Trio to listen. Lupin saw Black's name on the Marauder's Map, which Lupin helped to create when he was a student at Hogwarts. He is, in fact, "Moony" of the four Marauders. He saw someone else on the map with the Trio, but they are baffled as to who he means. Lupin and Black claim that Scabbers is actually an Animagus wizard... and that his name is Peter Pettigrew.
Harry, shocked by Lupin's apparent betrayal and overwhelmed by extreme emotions, is thinking and reacting illogically. He initially wants to execute Black, who even admits he was responsible for the Potters' deaths, though Black's demeanor and concern over Ron's injury belie his supposedly murderous intent. However, Lupin's timely and surprising arrival prevents Harry from harming Black, although it is doubtful whether Harry would intentionally kill or seriously wound him. Harry's underlying humanity ultimately prohibits him from performing violent acts, even against his enemies, unless it is to protect others. Only after Harry is forced to calm down is he willing to hear out Lupin, though Lupin's explanation that Scabbers is actually an Animagus Wizard seems too incredible to be believed.
Hermione also feels betrayed, having trusted Lupin and protecting his secret. If Lupin is lying and was actually aiding Black, by remaining silent, Hermione may have unwittingly doomed Harry. Lupin denies this, but given what is known about Black, we are having as hard a time believing this as Hermione, Harry, and Ron are.
Lupin's returning the Trio's wands, and then placing his own wand in his belt, is probably about the only thing that could have at least temporarily defused the situation; it shows that Lupin is secure enough in his own position that he believes himself able to convince he Trio by what he has to say, and believes that he will have no need to duel to make his points. By making himself effectively defenceless, he ensures that he will not be attacked until he is heard. This may, however, have repercussions later.
It has been noted multiple times that there were four Marauders, Moony, Wormtail, Padfoot, and Prongs. The revelation that Lupin, under his nickname Moony, is a Marauder, may lead the reader to suspect that Black, Harry's father, James, and Pettigrew, who we had earlier discovered were school friends, may be the other three. We don't yet understand the derivation of these nicknames, however.
Now that Black's Animagus form is known to be a large black canine, we may also wonder if he was the same dog that Harry saw near Privet Drive earlier, and during the Quidditch match against Hufflepuff, that he mistook for a Grim. If he was, and the author's economical writing style seems to imply that, just what was Black's true intent if he was not planning to murder Harry?
- What does Black mean when he says he is glad Harry acted like his father?
- What did Lupin, Pettigrew, and Black keep secret about themselves? Why?
- Why did Hermione never reveal Lupin's secret? How did she discover it?
- Lupin knew Black and Pettigrew were in the Shrieking Shack by using the Marauder's Map. How could he know how to use it?
- Why would Crookshanks attack Harry when he reaches for his wand, and why does he sit on Sirius' chest, refusing to be moved?
- Would Harry have killed Black if Lupin had not intervened? Explain why he would or would not have.
- How does Crookshanks know how to still the Whomping Willow?
- What might Lupin mean when he asks if Black "switched?"
As is usual in the Potter series, the book's climax ties up many plot elements, while also leaving questions open for future books. Rather than neatly wrapping up every significant revelation in a single chapter, the story-closing summations instead span three, and the principal characters' activities during this period take three more. The essential revelations are so dense that six chapters, about one third of the 22-chapter book, actually only cover a four-hour period in the story's overall timeline, though in fact three hours of that stretch are covered twice.
We have been told in this chapter that Sirius Black never intended to murder Harry, though this still seems doubtful; that Lupin also now believes Black never intended to harm Harry; that Lupin is a Werewolf and Hermione knew this; and that Peter Pettigrew, thought long dead, is actually alive in the form of Scabbers. The sudden change of perspective that this forces on us almost beggars belief; Harry clearly cannot believe it, and the reader also has difficulty with it, but every point will be corroborated in the next two chapters, not only by Black and Lupin, but also inadvertently by Snape. We will find that Black was convicted and imprisoned for a crime he never committed, and that Black feels responsible for Harry's parents' deaths, though he never betrayed them. Pettigrew being forced to resume his human shape will prove that Black did not murder him, which suggests strongly that the Muggles who died in that incident were killed by Pettigrew.
At Christmas, it was revealed that Black was Harry's godfather, and we will find that he has retained his affection for his godson. While Black was imprisoned, he wanted to know how Harry had grown up, and, after his escape, went to Privet Drive to try and glimpse Harry. He was at the Quidditch match to watch how well Harry could fly. On both occasions, he was in his Animagus form, the shape that Harry had believed to be a Grim. He was also in his Animagus shape the night that Harry saw him with Crookshanks.
In future books, it will turn out that Sirius becomes a large part of Harry's life. If there is any truth behind the smoke-and-mirrors fortune-telling that occurs in Professor Trelawney's Divination class, perhaps the putative Grim that Trelawney repeatedly finds in Harry's future is actually Sirius.
Scabbers is curiously intent on escaping, starting in the previous chapter where he seems to be trying to return to the concealment of the milk jug where Hermione had found him, to the point here where he manages to escape Ron's grip. Once we know who Scabbers really is, of course, his attempts to escape seem only logical; he is deathly afraid of being discovered by Sirius, who he had falsely accused of James', Lily's, and Pettigrew's death. It is a testament to the author's skill that the action of this chapter keeps us from wondering too much about why Scabbers is trying to escape.
- The Marauder's Map, created by James Potter, Sirius Black, Remus Lupin, and Peter Pettigrew, was first used earlier in this book to allow Harry to escape into Hogsmeade, and was later confiscated by Lupin; it has just shown Lupin, and will shortly show Snape, that people are getting into the Shrieking Shack via the tunnel under the Whomping Willow. After it is restored to him, Harry uses it to avoid interception by Peeves and Filch during Harry's fourth year; then, after it is borrowed by Professor Moody, it plays a role in Barty Crouch Jr.'s plot to murder his own father. Harry uses it to avoid detection of Dumbledore's Army, and himself, in Harry Potter and the Order of the Phoenix. It keeps Harry aware of Malfoy's activities in Harry Potter and the Half-Blood Prince. Finally, in Harry Potter and the Deathly Hallows, Harry uses the map to gaze at Ginny's name as she attends classes at Hogwarts.