Harry was extremely distracted that day, a fact that his friends could hardly miss as they took him around Diagon Alley picking up their school supplies. He actually made the clerk at Flourish and Blotts cry when, after the poor man had braved the cage full of Monster Book of Monsters to pick up three copies for Harry, Ron and Hermione, Harry distractedly muttered that he already had a copy from Hagrid, and it was only Mrs. Weasley's timely intervention that prevented him from coming away from Madam Malkin's with robes in every color of the rainbow. While Ron and his brothers were extremely taken with the Firebolt on display in the window of Quality Quidditch Supplies, Harry could hardly bring himself to take a look, and he was genuinely mystified when Ron snorted good-naturedly after Harry had sincerely assured Hermione that Crookshanks would make a very attractive pet, without so much as having glanced at the creature.
Harry, of course, was still trying to piece out in his mind what it meant that Pettigrew had come out of hiding. He was desperate to talk to Lupin, since he felt that only the older man would be able to help him make sense of this crisis, and part of him was caught up in despair that the two of them had decided not to take the matter to Dumbledore before this. He wanted to confide in his friends, but they hardly had much privacy from Ron's large family, and besides, his thoughts were too unsettled for him to know what he wanted to say. He was, moreover, especially irked by all the safety measures that were being taken on his behalf, and the menacing poster of Sirius Black caused in him a sharp pang of guilt every time he passed by it. He knew in some way it was his own fault that Pettigrew had chosen to go public; if he had left the safety of the Weasleys' home then it could only be because he had grown apprehensive about being recognized.
Harry managed to calm down enough to enjoy dinner with the Weasleys and Hermione that night. No one mentioned the sudden reappearance of Peter Pettigrew, although that was certainly the biggest news event of the day. Harry knew this was probably out of deference to him, since no one, apart from Lupin and Black himself, had seen fit to mention Black and Pettigrew's connection to Harry to him, and the Weasleys probably assumed that he was entirely ignorant of it. Still, whatever the reason, Harry appreciated the opportunity to distract himself from the thoughts that had been hounding him all day since he'd seen the newspaper.
Harry's hypothesis that the Weasleys believed him to be completely ignorant of the connection between Sirius Black and himself was confirmed when he went downstairs to get away from Ron and Percy fighting over the latter's headboy badge in the next room, and found Mr. and Mrs. Weasley fighting over whether or not he should be warned about Black coming after him. Harry remained in the dark bar area, wondering what Mrs. Weasley would think if she found out that Black had come for him already, and that through him, Harry had discovered a new connection to his parents. His heart clenched in that familiar way as it had all morning, and he wondered what he would do to extricate Sirius from this new conundrum, wondered once again where Sirius even was. And it occurred to him suddenly that he was thinking of Sirius, not Black. Not once this entire day had he considered that Pettigrew might be telling some manner of the truth. He had told himself this entire while that he awaited proof of Sirius's innocence, but now, as it became apparent that proof might be difficult to come by, he realized that he didn't require it any more. He believed Sirius, he wanted to defend him to Mrs. Weasley, and the whole world, but first he needed to figure out how he could prove his innocence.
The following day, Harry hardly had a chance to think in the morning as the large party rushed to get ready in time for the train. If they didn't have the Ministry cars escorting them they might well have been late, and by the time Harry got on the train, after he had been pulled aside by Mr. Weasley for a confidential warning that had him feeling all the more guilty, it was nearly about to leave. Ron and Hermione had waited for him, and they found that most of the compartments were already full, until they found one at the end of the train that was nearly empty.
"Professor Lupin!" Harry exclaimed loudly, entering the compartment. He was slightly embarrassed a moment later as Lupin looked up, groggily, showing clear signs of exhaustion.
"Sorry, I shouldn't have disturbed your rest; I'll let you get back to sleep," he said, but Lupin was already sitting up, smiling at Harry and his friends
"No, it's good to see you, Harry. Come in, sit down."
As Harry and his friends took their seats, Lupin stretched and seated himself again, greeting Harry's friends affably. Hermione showed signs of wanting to monopolize the conversation, very interested in speaking to a teacher at such close quarters, and especially one of whom Harry had written so warmly. Harry, however, was too preoccupied with his own worries to allow her to monopolize the conversation in this way.
"Professor," he interrupted, "I think we need to talk."
Lupin looked up, his eyes alert, despite his fatigue.
"Have you updated your friends about any of this yet, Harry? And what about…?" his eyes flicked to Ron, meaningfully, as though there was something he was unwilling to say out loud.
"Well, no. I haven't had a chance to talk to them quietly. But we really need to talk now. Especially given recent events, it throws all our plans off."
"What recent events?" Lupin looked mystified.
"You mean you haven't heard? It was all over yesterday's Prophet!"
"I've been… out of sorts for the last day or so. I'm still recovering, really. I haven't seen anything. You don't mean they've caught…"
"Merlin, no! But it's nearly as bad. Pettigrew's back."
"And what about…?" His eyes flicked to Ron again, and this time Harry understood what Lupin meant.
"Oh, Scabbers disappeared, of course, in Egypt, where Pettigrew turned up."
"So he was right then."
"Yes, but this doesn't help us any."
Ron and Hermione were looking at the two of them, completely flummoxed by the strange conversation. Lupin smiled suddenly, sitting back.
"At least we can talk freely in here, then. Harry, if you're planning to tell your friends about this why don't we take the story from the beginning? I'm not sure I ever got the full details from you, either, and I certainly haven't heard about these developments. Just give me a moment." He pulled out his wand and cast a couple of enchantments on the door, then turned back to give Harry his full attention, "It'll keep anyone from overhearing us, and give a bit of a warning if there's someone coming."
All of them were looking at Harry now. He told his story from the beginning this time, with Ron and Hermione frequently exclaiming at his foolhardiness, and wondering at the danger he had put himself into. Lupin was quiet, though, and Harry privately felt that his presence kept at least Hermione from expressing her disapproval as vehemently as she otherwise might have done. At least she approved of his conduct in contacting Lupin, although even that was muted when she learnt about the secrets Lupin had kept. At length he recounted the events of the previous day, and at this his reaction was immediate and violent. Ron swore loudly and feelingly, unable to contradict this apparent evidence that his pet rat had really been a traitor in disguise. Hermione, who had so far been skeptical of Harry's claims on Sirius's behalf, was also outraged. Lupin, who had broadly understood what Harry had meant earlier, looked thoughtful.
"I should have expected this. Harry, obviously you mentioned none of this to Ron in your letters, but is there anything that might have tipped Pettigrew off?"
"Well, I told him I'd met you, and that you'd started to tell me about my parents."
"That might have been enough, I'm afraid. He knows I know his secret."
"But what can he have been thinking? Isn't it going to raise a lot of suspicion, his reappearing like this, after all this time?" This was from Hermione.
Lupin shook his head.
"Peter always had a strong sense of self-preservation. That was partly why he stuck with James and Sirius, or at least I used to think that at the beginning, before we got to be good friends. And that may have been what drew him over to Voldemort, too. But he's also lazy, and he doesn't completely think things through before he does them. With any other person, I'd wonder at spending twelve years as a pet, but it fits with Peter, somehow. And now, I don't think he's fully considered that his reappearing actually reduces the charges against Sirius. All he's thought about is that somehow Sirius may have figured out where he is, and knowing that I'm coming back to Hogwarts, he may have thought that I could recognize him as well."
"But now that he's famous, won't Sirius know exactly where to find him?"
"Yes, that's exactly what he probably hasn't considered. I expect all he thought about was that it would be too comfortable being a street rat in Cairo. And he probably also enjoys the fame; he did always consider himself to be overlooked when we were younger."
"If he's the way you describe him didn't you know he'd be likely to let you down in something this important?" This was from Ron, always blunt and unambiguous in his emotions.
"It wasn't that simple, Ron. He was our friend, a good friend, we thought, after all that time. He certainly wasn't the most suspicious of us. I'd half-suspected Sirius for a time, although I certainly never thought he'd let James down until I heard of what had happened that Halloween. And Sirius had what I have to admit were fair reasons for suspecting me of the same. Peter was good at making himself innocuous. I'm still not convinced he did it out of premeditated hatred or betrayal. With him it's far more likely that one step just led to another."
"But what are we going to do about Sirius now?" Harry interjected. All this philosophizing was all very well, but he needed some kind of plan now, to protect his godfather.
"I think we can assume that if we don't manage to find him he'll go after Peter as he told you he would."
"Why is he such an idiot? Doesn't he see that this is proof that he couldn't possibly have committed the murder he was imprisoned for?"
"It's not so simple, Harry. The evidence is purely circumstantial, and that only for those of us who knew that Peter was an animagus. For the Ministry, there's rather a lot of dots to connect. And it wasn't just Peter, either; don't forget the twelve Muggles. And any eyewitnesses would have been obliviated years ago."
"So what are we going to do now?"
"I'll admit I'm tempted just to help Sirius along. That he could do this to James and Sirius – it's no less than he deserves."
There was steel in Lupin's voice, and Harry looked at him in a kind of horror. It was one thing to hear Sirius talk of such things, Sirius who fit everyone's mental picture of a ragged deranged convict, but this, from his mild mannered professor whom Harry had come to think of as being so very reasonable, was both chilling and moving. Harry hoped that he had this kind of loyalty for Ron and Hermione, but as much as he was no stranger to death and self-defense, he could not contemplate himself plotting cold-blooded murder on their behalf.
"You can't do that!" it was Hermione who made her outrage known.
"Of course not," Lupin agreed, in his usual mild tone, "for one thing, we're still left with the problem of finding him, and if we can manage that I'm sure we can come up with a palatable solution."
"Do you have any idea where he might be hiding?"
"There was one obvious spot which I've already checked, but then he'd know that I'd look for him there. Harry, you said that Hedwig's been finding him alright?"
"Yes, she always comes back without her letters, at any rate, and she seems pretty pleased with herself – I think she'd complain more if she hadn't found him."
"How long does it take for her to return when you send her?"
"A couple of days, usually. Why?"
"A couple days from Scotland means that she almost certainly is flying south. No where else on the British Isles would take that long, unless it were some of the more distant islands, like the Orkneys, but I doubt Sirius would return that close to Azkaban. And it's too short for the continent. Probably London, then, but it could be the Southern counties or even the midlands. London's easiest to hide in, though."
"Where in London, though?"
"Harry, when he offered to run away with you, did he suggest any places you might go to?"
"Well, he said he had a house, now that his Mum was dead."
"Yes of course, Grimmauld Place! He'd be well hidden there."
"You know his house?"
"I remember the address. I've never been; I wouldn't have been very welcome, I'm afraid. Sirius managed to get himself disowned when he was sixteen, and even before that he spent most of the summers at your grandparents', Harry. I don't believe the house was a very pleasant place."
"But will he have gone there, if you know where it is?"
"He may well have. He'd be very safe there; I'm sure there's all sorts of protections. Even though I know the address I'd have a hard time getting there, and an even harder time getting in."
"Will you go, then?"
"I might try, but there's a better way to try and get in touch with him if he's really there."
But Lupin didn't answer Harry's question directly.
"I think the time may have come to take Dumbledore into our confidence about this. I've broken into the Headmaster's office before, and I daresay I'm up for it again, but intractable problems have an uncanny way of becoming a bit easier when he knows what we're up to."