Grindelwald had already mapped out his entire plan. Once he arrived at Hogwarts, his first move would be to get on that cat's good side, figure out what Tom liked, then pander to those preferences and pull him into his own camp.
Sure, Tom was just a cat. But to Grindelwald, as long as someone was a wizard, they fell inside the circle he considered worthy. And as a Hogwarts student, Tom clearly counted.
The plan itself was solid. Reality, however, had other ideas. The very person Grindelwald needed most—Tom—ended up tangled up with the one man Grindelwald hated more than almost anyone else: Newt Scamander.
That left Grindelwald furious and completely helpless. After all, he had given Dumbledore his word that he had turned over a new leaf.
If he started fighting Newt over Tom now, it would be the same as openly admitting to Dumbledore that he had ulterior motives for coming back.
A lot had happened between them over the years, but Grindelwald had never forgotten their bond—and he had never wanted to cut it away. Age had mellowed him. The old hunger for power had faded, and what remained was a deeper appreciation for the connection they once shared.
Now, with a real chance to repair things finally in front of him, Grindelwald refused to rock the boat—at least not openly—until he had a fresh "marriage certificate" in hand.
So snatching a person—or a cat—out of Newt's hands was off the table.
Just as Grindelwald was ready to give up, Jerry appeared.
"A magical mouse," Grindelwald decided after a moment's observation. Originally he had planned to take advantage of his position as professor and simply watch Jerry from a distance, testing whether the mouse was as special as the cat. But the way Tom and Jerry had repaired the Great Hall that night—both the process and the result—made one thing painfully clear: if he didn't act first, he would lose his chance.
So he slipped into the Ravenclaw common room under cover of night, intending to build a rapport with the mouse while no one was paying attention. Best-case scenario, he would bring Jerry over to his side entirely. Worst case, he would at least plant enough doubt to make the mouse hesitate.
Jerry had no idea what was actually running through Grindelwald's mind, but he could feel the sincerity in the man's voice—and the honesty.
Maybe Grindelwald did have an agenda. But whatever that agenda was, it probably wasn't the usual villain scheme. Even if Jerry went along with him, the odds of becoming the next big bad were low.
Once Jerry realized that, his interest sparked instantly.
(What exactly do you want to do? Let's hear it.)
This was a chance to personally defeat Tom. Pretending he wasn't tempted would have been a lie. He had only refused earlier because he didn't want to turn into a villain. But if villainy wasn't required…
The mental image of finally beating that cat into the ground and making him kneel at his feet made Jerry squeak with pure excitement.
"So their relationship really is that complicated," Grindelwald noted to himself, watching the mouse light up. Luckily he had eavesdropped on the cat and mouse earlier. He already knew that while they were friends, they were also each other's greatest rivals. Without that knowledge he would have been completely out of ideas for recruiting Jerry on such short notice.
"Here's what I have in mind—"
Internally Grindelwald kept calculating, but outwardly he stayed calm. He cast a quick privacy charm so no one else could overhear, then laid his entire plan out for Jerry without holding anything back.
Even if Jerry turned around and told Dumbledore everything, it wouldn't matter. This new idea of his was not something that could be accomplished overnight. Even at the height of his power, with an army of followers, pulling it off would have been difficult. Now? The worst that would happen was Dumbledore watching him a little more closely.
And being watched by Dumbledore… was that really a punishment? No matter how this turned out, Grindelwald figured he wouldn't come out behind.
(If that's the case… I'll need to think about it. And my talent in this area is a little worse than that cat's.)
Jerry didn't agree right away, but Grindelwald could see the interest in those little eyes. He smiled—gentle and satisfied.
"There's no rush. Something like this requires deep magical mastery. I only brought it up so you'd know the possibility exists. I never expected you to pull it off overnight.
But before any of that… I could teach you a few useful things. How to make yourself invisible, for example. Or how to become someone else entirely."
(! I'll think about it—)
Jerry's mind flashed back to the handful of times he had managed to get the upper hand on Tom simply by being invisible. His heart started racing.
Invisibility was something he could already pull off with the special ink he had stolen from home before coming to this world, but that was still an external tool. If he could do it with his own magic…
And transforming into other people?
If he turned himself into his big cousin Spike, would Tom still dare act so cocky?
Just the thought made Jerry's little heart hammer.
Excitement was one thing, though. Something this big still needed careful consideration.
"Of course. Take all the time you need. Even if you refuse, you're still welcome to come learn those two spells from me."
Grindelwald's smile stayed warm. "This isn't payment. Consider it a gift from one kindred spirit to another, after we hit it off so well."
Jerry's tiny heart was thumping so hard it felt ready to punch straight through his chest. Looking at the sincere old man in front of him, he was terrified he might accidentally agree right then and there.
(I understand. If I need anything, I'll come find you, Professor Percival.)
"Call me Grindelwald. Gellert Grindelwald. That's my real name. Though I'd appreciate it if you kept it quiet for now. Only a few people know it at the moment, and Dumbledore is one of them."
If he was going to play the emotional card, Grindelwald saw no reason to hide anything from the mouse.
Unlike Credence, this little rodent couldn't use Legilimency. But Grindelwald's Occlumency was excellent, and he could still sense that Jerry possessed a natural instinct for reading emotions. Even his best mental defenses could only detect the ability—they couldn't block it. To open Jerry's heart faster, honesty was the best approach.
(Got it.)
With that, Jerry spun on his short little legs and scampered away as fast as he could. If he stayed any longer he was genuinely afraid this old man would charm him into agreeing without him noticing.
"Is this what they call masculine charm? It's terrifying!"
Jerry muttered to himself the entire way back.
Grindelwald watched the mouse disappear, his smile fading into something colder.
Newt had once blindsided him. Fine. He accepted that loss. But with careful training, his own heir would absolutely even the score against Newt's chosen one.
"Achoo!"
In the Hufflepuff dormitory, Tom suddenly sneezed hard. For some reason he had the distinct feeling someone was watching him.
"That stinky mouse again? What's he plotting this time?"
Tom ran through every possible scheme Jerry might be cooking up. The more he thought, the heavier his eyelids grew.
Whatever. Future problems could be future Tom's headache. Right now—
Sleep!
With that final thought, Tom drifted into a sweet, dreamless rest.
Over in the Gryffindor common room, the usually empty hall was currently occupied by three—no, four—figures.
"Hermione, are you sure you've seen the name Percival before?"
Ron's voice was thick with exhaustion. "You started digging through every book we used last year the second we got back. Don't forget we've got classes first thing in the morning!"
"I know, but—"
Hermione stared at the mountain of books that was already taller than any of them and bit her lip. "I'm certain I saw that name while we were researching Nicolas last year. I just can't remember exactly where."
"Maybe he's like Nicolas—someone from way further back in history?"
Harry offered.
"…I don't know. It's possible."
Hermione still felt like something was off, but she genuinely couldn't place the name.
Ariana, who had more or less figured out the new professor's real identity from the way Dumbledore and the man kept making eyes at each other, simply yawned and squatted off to the side, looking thoroughly bored. She neither helped nor refused Harry's group's requests.
If these kids ever found out their current Defense Against the Dark Arts professor was the original Dark Lord himself, who knew what chaos they would cause?
"Ariana, give me a hand!"
"Coming~"
As long as her brother was around, he would handle everything. There was no need for her to worry.
With that comforting thought, Ariana drifted over at a leisurely pace and resumed her dedicated slacking.
Come to think of it, Professor Newt and Tom had both asked her to drop by when she had free time. She still had no idea what they wanted.
Whatever. She could figure that out later. Right now she was busy being a ghost with zero responsibilities.
Slytherin House, meanwhile, had not spent the evening at the Ravenclaw table enjoying the feast, so they had no idea Harry's group was already suspicious of the new professor. That didn't mean Draco was having a peaceful night.
His growing friendship with Harry and the others had already strained his relationships with Goyle, Crabbe, and Pansy, but pure-blood families still maintained a surface-level civility.
Tonight that thin veneer finally tore completely.
Using his connection to Tom to recruit first-year students looked, to the older pure-blood supremacists, like outright betrayal.
After all, Tom wasn't even human—let alone pure-blood.
No one was going to claim Tom was the product of some extremely adventurous pure-blood heir.
Even if that were somehow true, they still wouldn't accept him as pure-blood. Pure-bloods were the sort of people who erased Squibs from the family tree just to protect the superiority of their bloodline.
Draco could not have cared less what those fossils thought. With a school governor for a father, none of them could do anything to him while he was at Hogwarts.
And outside Hogwarts?
With Lucius Malfoy at his back, he had even less reason to fear a bunch of loudmouths who only ever barked at their own kind.
Besides, Slytherin was different from the other houses. Each year group operated independently, and each year had its own leader.
Last year, thanks to the points he earned and the fact that he had helped secure Slytherin's seventh consecutive House Cup (even if it was only a quarter of the cup), Draco's position among his year was already unshakable.
There were still a few like Pansy who opposed him, but they were irrelevant.
Now, with Tom's name as leverage, he had already pulled a decent number of first-years into his orbit. If things continued this way, next year's first-years might look to him as their leader as well.
Under those circumstances, did those older Slytherins seriously think they could still threaten his position? Impossible.
The only real danger was that the upper-years might abandon all pretenses of "Slytherin honor" and simply use force to crush him.
So Draco spent the night carefully planning how to ask Tom for help—or at the very least, how to get some life-saving tools or techniques out of the cat.
On top of that he had to tally the new students' requests and figure out what kind of bribe would actually move Tom.
In short, it was a completely sleepless night for Draco as well.
And just like that, the new term's first night of heavy thoughts came to an end. Aside from Tom, almost no one got a proper rest.
The next morning, sunlight streamed through the Great Hall's enchanted windows exactly the same as always, falling across the four long tables.
At the Hufflepuff table a cluster of bleary-eyed students had already gathered.
"So what exactly did you all do last night? Why do you look like you got hit by a Bludger?"
Tom, who had slept like a baby, stared at his friends' twin sets of massive dark circles and felt a giant question mark form over his head.
"Maybe they just can't sleep in new beds?"
Luna, who had also slept perfectly well, spotted the familiar faces at the Hufflepuff table and walked over without the slightest hesitation, settling herself right beside Tom.
"Hey, Tom. Good morning~"
Jerry, still mulling over Grindelwald's words, hadn't forgotten his own original plan. So when Tom looked up, he found a pair of equally dark-circled mouse eyes poking out from over Luna's shoulder.
"?! Jerry!!!"
Okay. Tom had to admit it. That was a brutal move. He could not tolerate it even a little.
He had considered the possibility that Jerry might hitch a ride with some other Ravenclaw. But why did it have to be Luna?
If it had been anyone else, Tom might have written it off as coincidence. With Jerry, though—
"You did that on purpose. You absolutely did that on purpose!"
Jerry only grinned and hopped down from Luna's shoulder.
"? Is he… taunting me?"
If Tom could put up with this, he didn't deserve the name Tom.
And just like that, first thing in the morning, the living disaster duo launched into another Great Hall chase.
Unlike the day before, Jerry had Grindelwald's backing now—whether or not the old man was trustworthy—and that made him a lot bolder. At the very least, he no longer bothered dodging the other students while he ran.
In the blink of an eye the entire Great Hall descended into chaos, student screams rising one after another.