Hannah Abbott's comment successfully caught Jon's interest.
Now that Lockhart had left, who would be the temporary Defense Against the Dark Arts teacher?
There were still nearly four months left in the semester—they couldn't just leave all the students without a teacher for one of their core subjects!
After all, Hogwarts didn't have assistant instructors for Defense Against the Dark Arts. It was already hard enough to find a proper teacher, let alone an assistant.
Could it be that Dumbledore was bringing in Remus Lupin ahead of schedule?
That was a possibility. But with the curse Voldemort had placed on the position, something was bound to happen by this time next year anyway!
The speculation helped pull Jon out of the frustration he'd been feeling over his failed attempts to cast the Patronus Charm.
He'd specifically gone to ask a few second-year Hufflepuffs who had just attended Defense Against the Dark Arts that morning.
"Sorry, Jon, I can't tell you!" said Ernie Macmillan. "The temporary Defense Against the Dark Arts professor told us not to go around spreading his name... All I can say is—he's amazing!"
Jon pouted and dropped the subject.
At lunch, he overheard nearly everyone in the Great Hall speculating about who the mysterious substitute professor might be.
"I think it could be Alastor Moody!"
Passing the Gryffindor table again, Jon heard Ron Weasley shouting,
"That Auror—Mad-Eye Moody! My dad told me he and Dumbledore are really good friends. And it's quite the coincidence—he retired from the Auror Office at the Ministry just two months ago!"
"I don't care who it is, as long as it's not Snape..." Harry Potter muttered. "You know he's been after that job for ages."
"I think the Ministry might send someone in," Hermione Granger said, frowning. "They just declared our Defense Against the Dark Arts professor a wanted criminal a few days ago—maybe they'll send a Senior Undersecretary to manage the situation?"
As he quietly passed their table, Jon didn't bother guessing further.
He'd find out soon enough in the afternoon class.
During lunch break, Jon didn't return to the Hufflepuff common room. Instead, he went back to the Room of Requirement.
He spent over an hour practicing the Patronus Charm again—without success.
The results were still discouraging. He just couldn't find a truly happy memory to focus on. It looked like mastering the Patronus Charm was going to take more time.
It wasn't until just before two o'clock that he rushed down from the eighth floor to the Defense Against the Dark Arts classroom on the fourth.
Luckily, he was quick on his feet and the staircases didn't give him any trouble. He made it just in time.
As he reached the classroom door, he was startled by loud cheers from inside.
"What's going on?" he muttered, stepping in, confused.
Zacharias Smith was standing on a stool, whistling.
In fact, barely any students from Hufflepuff or Slytherin were sitting down. Almost everyone was on their feet, cheering and celebrating.
At the front, a white-haired old man stood at the podium, smiling and waving to quiet them down.
It was a familiar face...
Jon was stunned.
The temporary Defense Against the Dark Arts teacher...
Was Albus Dumbledore!
...
It took several minutes for Dumbledore to settle the class down.
"I suppose... I don't need to introduce myself?" he said with a wink.
Laughter echoed through the room.
"Professor Lockhart has left us due to... certain special circumstances. And finding a substitute in the middle of the term isn't easy," Dumbledore explained calmly. "So I thought, perhaps I could fill in for a while."
"To be honest, it's been fifty years since I last taught... and the last time I taught Defense Against the Dark Arts was way back in 1927," Dumbledore said with a smile. "Back then, I had a bit of a disagreement with the Ministry. They banned me from teaching the subject, and I was forced to switch to Transfiguration."
Seeing how every student in the room was listening closely to his story, Dumbledore waved his hand lightly.
"Old stories—best left alone. But I still remember the last Defense Against the Dark Arts lesson I gave sixty-six years ago. And today's lesson will be the same."
"So, let's begin... Please put your books away. In Defense Against the Dark Arts, we focus on practical work—you'll only need your wands."
The students quickly returned their books to their bags, many exchanging excited looks. They had been at Hogwarts for more than half a year and had never had a practical Defense Against the Dark Arts lesson.
"Now, follow me..."
The students got to their feet and followed Professor Dumbledore out of the classroom. He led them through a quiet corridor, around a corner, and into an unfamiliar classroom.
It was empty, except for a row of old benches along one side.
At Dumbledore's signal, the Hufflepuff and Slytherin students sat down in order.
Jon instinctively chose a seat near the back—it was easy, since everyone else was rushing to sit up front.
Professor Dumbledore had already drawn his unique Elder Wand.
With a wave, a wardrobe nearly twice the height of a person appeared in the middle of the room.
He walked up to the wardrobe and stood in front of it. Suddenly, the wardrobe began to shake, as if something inside was trying to break free.
"Don't worry!" Dumbledore said calmly when a few students flinched in fear. "It's just a Boggart!"
"Boggarts like dark, enclosed spaces. Under beds, inside wardrobes, even cupboards—they love hiding in such places. So, my first question to you is: what is a Boggart?"
A girl in the front row quickly raised her hand.
"Very good, Miss Selwyn!"
"No one knows what a Boggart actually looks like—it transforms!" said the Slytherin girl, Selwyn, who carried herself with a touch of arrogance. "It becomes whatever we fear most."
"I couldn't have said it better myself," said Professor Dumbledore with a nod. "Five points to Slytherin."
Selwyn sat down happily, drawing envious glances from nearby students.
"No one knows what a Boggart looks like when it's alone," Dumbledore continued. "But once I release it, it will instantly become the thing each of us fears most."
"Now, everyone take out your wands..."
"Let's try a spell:"
"Riddikulus!"