“There!” said Pettigrew shrilly, pointing at Ron with his maimed hand. “Thank you! You see, Remus? I have never hurt a hair of Harry’s head! Why should I?”

“I’ll tell you why,” said Black. “Because you never did anything for anyone unless you could see what was in it for you. Voldemort’s been in hiding for fifteen years, they say he’s half dead. You weren’t about to commit murder right under Albus Dumbledore’s nose, for a wreck of a wizard who’d lost all of his power, were you? You’d want to be quite sure he was the biggest bully in the playground before you went back to him, wouldn’t you? Why else did you find a wizard family to take you in? Keeping an ear out for news, weren’t you, Peter? Just in case your old protector regained strength, and it was safe to rejoin him . . . ”

Pettigrew opened his mouth and closed it several times. He seemed to have lost the ability to talk.

“Er—Mr. Black—Sirius?” said Hermione.

Black jumped at being addressed like this and stared at Hermione as though he had never seen anything quite like her.

“If you don’t mind me asking, how—how did you get out of Azkaban, if you didn’t use Dark Magic?”

“Thank you!” gasped Pettigrew, nodding frantically at her. “Exactly! Precisely what I—”

But Lupin silenced him with a look. Black was frowning slightly at Hermione, but not as though he were annoyed with her. He seemed to be pondering his answer.

“I don’t know how I did it,” he said slowly. “I think the only reason I never lost my mind is that I knew I was innocent. That wasn’t a happy thought, so the dementors couldn’t suck it out of me . . . but it kept me sane and knowing who I am . . . helped me keep my powers . . . so when it all became . . . too much . . . I could transform in my cell . . . become a dog. Dementors can’t see, you know . . . ” He swallowed. “They feel their way toward people by feeding off their emotions . . . They could tell that my feelings were less—less human, less complex when I was a dog . . . but they thought, of course, that I was losing my mind like everyone else in there, so it didn’t trouble them. But I was weak, very weak, and I had no hope of driving them away from me without a wand . . .

“But then I saw Peter in that picture . . . I realized he was at Hogwarts with Harry . . . perfectly positioned to act, if one hint reached his ears that the Dark Side was gathering strength again . . . ”

Pettigrew was shaking his head, mouthing noiselessly, but staring all the while at Black as though hypnotized.