From Azkaban to Hogwarts.

However, just as everyone was laughing hysterically at this not-so-funny topic, the child who had spoken was dumbfounded, frozen in place as if he had been petrified.

"how--"

The students next to him tried to tap him to see what was wrong, but instead saw William smiling at them while holding a bunch of snacks.

"Ah, hello professor!"

"Hello to you all as well."

William nodded. "The snacks on the train are pretty good. You should try them."

He flicked his left hand, sending several food items flying up and landing on a table among the students. "By the way, remember to close the door to the private room next time you have a discussion. I understand the feeling of being on holiday, but it's not good to be too noisy."

After finishing all this, William, carrying his snacks, strode towards his private room, leaving the students looking at each other in bewilderment.

Honestly, if he weren't worried about the limited-edition food items on the food truck selling out, he wouldn't have bothered to disturb the students' happy time.

Ignoring the students behind him who were speaking in hushed tones, William pointed to his private room, then went inside and placed the snacks on the table. "Professor Lupin, it's time to eat."

However, unlike William's joy, Lupin was somewhat nervous. He picked up a bag of flavored beans but didn't open the package. "Is Mr. Belby really coming?"

“I am quite certain, Professor Lupin.”

William nodded. "There's no need to be so nervous, Professor Lupin. I know you think Professor Belby is amazing, even that he's been kind to werewolves, but honestly, he doesn't like that kind of thing."

“Furthermore,” William lowered his voice, “I can tell you secretly that we are about to conduct a somewhat dangerous experiment, and we need your help.”

"help?"

Lupin didn't even ask where the danger was, but rather, "What can I do?"

“A lot, a great deal, and I will minimize the danger,” William said, looking at Lupin. “Simply put, we are going to make some improvements to the existing wolfsbane remedy because we have discovered an interesting phenomenon that can be integrated into the remedy.”

"I need to participate in drug trials? Absolutely."

Lupin nodded decisively.

“No, it’s impossible to achieve that level in such a short time…” William quickly waved his hand. “It’s just that there are some things that require your cooperation.”

He wouldn't rashly let Lupin test the drug—not to mention that the drug is still in its infancy, even if a finished drug were available, William would have already selected the most suitable test subject long ago. How could he let Lupin be in charge of such a dangerous task?

"I'm fine with whatever you do."

Lupin's voice was soft, but extremely firm.

"Okay, okay, you've got your work covered."

Seeing that he couldn't persuade Lupin, William shook his head. He needed to communicate with Moody as soon as possible. He had originally wanted to wait until the medicine was ready before talking to him, but judging from Lupin's momentum, he didn't seem to want to wait any longer.

The self-defense course was finally getting on track, and he had no intention of sacrificing his colleagues.

-

"Professor William, is Professor Belby really coming?"

At the final stop, Sirius, who had come to pick him up, excitedly hugged Lupin and then asked William in a low voice.

"Yes, it's today. He's already in London. I'll go to Diagon Alley to pick him up later—he flew there using FlooNet."

"Oh, this is really... really rude."

Sirius seemed just as nervous as Lupin—the inventor of the wolfsbane potion was visiting him, and incidentally, he wanted to improve the potion, which made it difficult for him to remain calm.

If it were just him, he might simply be polite to the professor, and whether he would agree to the professor disrupting his life was another matter. But there was also Lupin.

"Don't worry, Mr. Bellby has been everywhere; he knows London very well..."

"That won't do, that would be too rude. Let's go pick them up now..."

“But Harry hasn’t come out yet,” William glanced around, making sure he didn’t see Harry, then pulled over a student to ask, and quickly got the answer—Harry was saying goodbye to his girlfriend…

"What time is it already..."

Sirius was getting a little anxious, then he saw a familiar figure. "Hey, Arthur!"

Mr. and Mrs. Weasley also came to pick them up. Sirius called them over and greeted them warmly. After exchanging a few pleasantries, Sirius asked in a somewhat apologetic tone, "Excuse me, Arthur, I have urgent business to attend to. Could Harry stay at your house for the night?"

"Want to stay here?"

Mr. Weasley paused for a moment, then smiled. "Of course, of course, no problem, as long as it takes."

"That's great."

Sirius answered with a sigh of relief, then nodded to William, his eyes even carrying a hint of urging.

'That's too hasty...'

William shook his head helplessly, but Harry was still safe at the Weasleys' house—Harry had stayed there a long time ago, and Dumbledore trusted him.

It's a bit of a shame that Sirius is letting Harry stay here, so he can't remind the Weasleys to keep an eye on the twins—as their professor, he's clearly noticed that the frequency of their pranks has decreased recently.

Aside from the almost impossible scenario of the two suddenly changing their ways, there's only one other possibility left—the two are brewing a huge conspiracy.

"Oh, right... I also need to tell Dumbledore that Harry will be staying at the Weasleys' house for the night... Although the Weasleys are trustworthy, these are special times..."

He found an owl post office nearby and sent the letter to both Professor McGonagall and Dumbledore, so that if Dumbledore was slacking off, Professor McGonagall could relay it immediately.

"Let's go pick up Mr. Bellby."

After he finished his work, the three of them found a secluded spot and began to Apparate.

-

“I will write to you every day.”

Harry, carrying Hedwig, looked at Cho Chang and spoke about a topic that would enrage the owl.

However, neither of them expected that the owl they had worked so hard for would leave them behind—when they were in school, they could see each other every day, no matter how busy they were, but now that they were on vacation, they could only communicate with the owl…

They talked reluctantly until most of the crowd had dispersed before they reluctantly headed towards the exit.

It was then that Harry remembered a serious question.

'We're doomed! Sirius, Lupin, and the Professor X! They must have been waiting forever!'

Thinking about this, Harry felt a pang of guilt; he had completely forgotten about the time!

'I'll be laughed at to death, whether it's Lupin or Sirius…'

Filled with despair and guilt, he even started jogging and hurriedly ran towards the exit. However, when he looked up, Sirius, Lupin, and the professor were nowhere to be seen.

Is it a joke? Or...?

He couldn't help but reach for his wand, but out of the corner of his eye, he spotted a redhead resembling Ron, who looked incredibly familiar.

He was less anxious at first, and carrying his suitcase, he walked over there. He had lived with the Weasleys when he was in second grade and liked them very much.

“Harry”.

Mrs. Weasley smiled kindly. "Is it all over?"

The question was rather ordinary, but Harry couldn't help but blush.

My suitcase is open…

He lied somewhat awkwardly, saying, "It took some time to process."

“By the way,” Harry began to forcefully steer the conversation toward the converter, hoping to avoid discussing the awkward matter, “have you seen Sirius Black? I haven’t found him.”

“It was Sirius who entrusted it to us,” Mrs. Weasley said with a kind smile tinged with a hint of teasing. “He said he had important business to attend to, so you can stay at our house for the night and keep Ron company.”

Where is Ron?

"He hasn't come out yet—his box has probably been opened by now."

-

“The house is a bit messy, I hope you can get used to it, Mr. Belby.”

Sirius Black, as the host, welcomed him, but Mr. Bellby was more anxious than he had expected.

"Can I see the lab first?" he asked Sirius before even putting down the box. "I spoke with Professor William; to properly adjust the potion, we need a more robust lab. I brought all the equipment and a lot of raw materials, but the lab needs to be absolutely secure..."

Magical experiments don't involve any fancy equipment, but sturdiness is essential—experimental accidents are too easy to happen, and could even send a house flying into the sky.

"It has been converted from a basement, the protective measures are in place, and the quality is excellent."

Sirius nodded—this kind of problem, which could be solved with Galon, wasn't that difficult for him.

"That's great, let's go check it out first."

Belby was about to head to the lab with great speed, and the others didn't try to stop him. They took the boxes and went straight to the basement.

"Very good, very good. With a little reinforcement using magical materials, it's practically top-of-the-line for a personal laboratory."

As he praised it, he opened his briefcase—the space inside had been magnified many times over by the Seamless Expansion Spell.

“Take a look at my instruments, Professor William, how about this crucible!”

While waving his wand to occupy the laboratory table, Belby showed off to William—others certainly wouldn't understand, so showing off to those who knew was the right thing to do.

"Wow, are these German-made crucibles?"

William's eyes lit up. "A masterpiece?"

"That's right, good eye!"

He laughed and then introduced his instruments one by one.

...

"Alright, the initial phase is complete!"

"Great! Is there anything else I can help you with?"

Although Lupin didn't quite understand much, he still volunteered to go forward.

“Well… Professor Lupin, we will be there when needed,” Mr. Bellby hesitated for a moment, then turned to Sirius. “It’s not appropriate to be too explicit in the letter. Mr. Black was the main force behind this research improvement, and Professor William and I were just assisting.”

"I?"

Sirius paused for a moment, then laughed, "Anything is fine, I'll cooperate fully."

"That's great!"

Chapter 575 A successful experiment requires the cooperation of many people.