Albus Dumbledore did not agree to Professor Lockhart's suggestion. Not only had the new Defence Against the Dark Arts professor already been found months in advance, but even if the position were empty, he would never let Gellert Grindelwald teach it. His reason was the same as his staunch refusal to allow Tom Riddle to remain at the school: he worried about corrupting the young minds. In terms of negative influence, Tom was, in Grindelwald's presence, merely a Junior Jinxer. Grindelwald was the kind of wizard who, wherever he went, could instantly gather a loyal following of supporters. Even in prison, during his decades confined in Nurmengard, Merlin only knew how many house-elves had been swayed, replaced time and again, making it impossible to guard against him.
However, Lockhart's suggestion did give him pause. Now, the only place capable of properly holding Grindelwald, preventing him from wreaking havoc, was perhaps Hogwarts School of Witchcraft and Wizardry. Dumbledore found himself with a splitting headache. He had, in truth, avoided such matters before, believing that should he suddenly die one day, this so-called Nurmengard prison would no longer be able to contain Grindelwald, and then Grindelwald's confinement would no longer be his concern. Yes, he had, to some extent, been avoiding it. He didn't want to kill Grindelwald, yet he couldn't release him, so he simply kept him imprisoned until the day he himself would pass away. He had lived long enough; it would be soon. Then Gellert would be free, and if the world had the power, they could deal with him. If not, they could simply follow Gellert's guidance. What else could be done? He'd be dead and couldn't concern himself with such things.
But then, a small complication arose. That wretched Tom Riddle appeared, forcing "the greatest wizard of this century" to once again shoulder this burden, to face and to fight. Nearly fifty years had passed in the blink of an eye. Grindelwald had been confined in Nurmengard Castle for almost fifty years, but had Dumbledore himself not been confined within Hogwarts Castle, enduring these long years, day and night?
Dumbledore gazed at the collapsing Nurmengard Castle with a complex expression, suddenly feeling a strange malevolence from fate itself—it always urged him to confront, to confront, to confront all pain! Sigh. Sometimes he truly didn't want to shift the blame onto others, but he genuinely felt that Lockhart's appearance had indeed changed things. What vexed him even more was that he distinctly felt the two behind him exchanging malicious glances.
"Young man, you ought to show some respect for your elders," Gellert's voice was low, but Dumbledore heard it, it was hard not to.
"Hah," Lockhart sneered, his voice equally low. "It's rather hard to respect an elder such as yourself."
"Don't let me get my wand, I'll finish you off!" Gellert's voice was vicious.
"Oh? Is that so? My apologies, but you'll have to get in line if you wish to finish me off," Lockhart chuckled. "Since you're a seer, why don't you try a divination and see what I'll do to you in the future?"
"Ha! Come on then, try it!" Gellert, it seemed, was growing more childish with age, even challenging him like a small child.
"Enough!" Dumbledore growled, turning to glare coldly at the two troublemakers causing him such a headache. "Both of you, silence!"
Ah, at last, the world fell silent.
He began to clean up, waving the Elder Wand to repair the ruins before them, even though it could no longer serve as a proper prison. Spell after spell was cast: Anti-Recall Charm, Detection-Proof Charm, Anti-Snooping Charm, all in an attempt to cover up the incident. He had no choice; if the world knew Gellert had escaped Nurmengard, there was no telling what panic and chaos it would unleash.
Having finished, he turned back, gazing at Gellert with a complex expression, exhaled deeply, and waved his wand to dispel the restraints on the former Dark Lord. "Both of you, follow me."
Fawkes, the phoenix, soared, engulfing them in a blaze of fire. After the flash, all three figures vanished.
They first arrived at the Hospital Wing, where Monmondo, the house-elf, had already brought Crabbe to receive treatment. The increasingly elderly Madam Pomfrey had not left school for the holidays and was currently brewing a potion for the unconscious boy. Seeing them approach, Madam Pomfrey spooned the potion from the cauldron into a cup and placed the cup in a copper basin filled with ice water to chill it. "There's nothing seriously wrong; he just needs rest." As she spoke, she occasionally glanced at the thinly clad figure among the three, a look of bewildered surprise on her face.
"Poppy, long time no see," Grindelwald's expression softened considerably.
"It truly is you!" Madam Pomfrey exclaimed, growing excited. "Has Dumbledore released you?" Yes, Madam Pomfrey had once been a Saint (a follower of Grindelwald). In those turbulent bygone years, she and Dumbledore were merely colleagues, and her co-workers at Hogwarts didn't influence her to side with old Dumbledore.
"How is your Muggle husband doing now?" Grindelwald always remembered such details about his followers.
"He's passed on," Madam Pomfrey smiled, shaking her head, not overly concerned. "He left peacefully, surrounded by his grandchildren, even telling them stories before he went."
"Grandchildren..." Grindelwald seemed a little wistful. "Time truly flies. I remember you bravely trying everything to be with your Muggle husband." In that era, the union of a wizard and a Muggle was no easy feat, and now, to think she had grandchildren.
Professor McGonagall, who had arrived, her face initially solemn, observed the scene, her lips pressed together, her gaze softening. Indeed. So much time had passed. Some things were long buried in the dust, no longer so important. She turned to Lockhart with a puzzled look. Lockhart shrugged innocently. "Mr. Grindelwald and I had a bit of a disagreement in Nurmengard, and then, well, the castle accidentally collapsed."
"!!!" Professor McGonagall froze, blinking, a little unsure of what she had just heard.
Dumbledore, who was checking on Crabbe, looked back at Professor McGonagall and Madam Pomfrey. "He'll be staying at Hogwarts from now on..."
Professor McGonagall gasped. "You intend to bring him to Hogwarts? Are you certain he won't cause trouble at the school?"
Dumbledore looked rather helpless. "I'll keep a close eye on him."
Professor McGonagall clearly did not approve. "I think our busy Headmaster has forgotten something: do you even spend a third of your time at the school in a month?"
Indeed. Dumbledore was incredibly, incredibly busy. He couldn't possibly abandon his crucial duties at the International Confederation of Wizards, where many decisions would profoundly impact the development of the entire wizarding society. And implementing those decisions through the British Ministry of Magic, even with Minister Fudge and wizards like Kingsley Shacklebolt and Arthur Weasley there, required his constant oversight. Not to mention the search for Lord Voldemort's Horcruxes, which Dumbledore had poured immense effort into over the past school year. And then there was the ongoing search for the next Defence Against the Dark Arts professor; that was also something that absolutely had to be done. It was simply a lot of trouble. Even before Remus Lupin had come to take over as the Defence Against the Dark Arts professor, Dumbledore was already scouting candidates for the year after next. Dumbledore had far too much on his plate! And yet! He claimed he would keep an eye on Grindelwald?
"I'll have someone keep an eye on him. In fact, I've found a very suitable candidate," Dumbledore said, his gaze shifting to Lockhart. Immediately, everyone present turned to look at Lockhart.
"Me?" Lockhart pointed at himself, disbelievingly.
"You destroyed Nurmengard! You must take responsibility!" Dumbledore's tone was somewhat domineering, even subtly vexed. "You weren't the only one to visit him in nearly fifty years, yet you alone destroyed Nurmengard! Whatever happened behind it, that is the fact."
What in the blazes?! Is that what you're saying? This is hardly fair!
Lockhart was rather displeased. "I was planning to travel the world!"
"I'll keep Grindelwald by my side until the start of term," Dumbledore said, smiling. "You'll have plenty of holiday time."
Lockhart rolled his eyes, muttering discontentedly. After a moment's thought, he looked at Grindelwald and finally nodded. "Alright, but I have a condition."
"Speak it," Dumbledore didn't mind suggestions.
"I want to learn castle-building magic. You have to teach me." This kind of magic, Lockhart realised, he couldn't really learn anywhere else apart from Dumbledore. "Then I'll find a way to completely repair Nurmengard Castle, so this fellow can be locked back inside if necessary!"
"What?!" This time, it was Grindelwald who was displeased. "Young man, do you hear yourself?"
"Agreed!" Dumbledore immediately accepted, smiling at the two of them. "But I don't have that much time to teach you. In fact, when it comes to castle magic, Gellert is the most skilled. Nurmengard Castle was built by his own hand. I'll make him teach you everything he knows, without holding back."
"!!!" Grindelwald's eyes widened. What? He was to teach this young wizard castle magic, only for this person to repair the very castle that imprisoned him? Dumbledore, do you hear yourself?!
"It's settled then!" old Dumbledore's voice was quite firm.