Harry and Ron were surprised to find a secret passage at the base of the Whomping Willow, which bore a striking resemblance to the Basilisk's Chamber of Secrets.
Several diamond-shaped rays of light pierced through the gnarled tree roots. Harry could vaguely discern the directions, sometimes sliding down and sometimes grabbing onto the roots to climb up.
The exit was small, emitting a faint, scattered light. Harry kept making sure his wand was in his sleeve. He poked his head out of the exit first, looking around to make sure no one was nearby before slowly climbing out and pulling Ron up with him.
"This looks like the Shrieking Shack," Ron dusted himself off, then continued patting Harry's back (which Harry couldn't reach), "We're back in Hogsmeade."
Having been exposed to the Chamber of Secrets of Secrets, Harry first observed his surroundings. He rubbed the dust off the floor with his finger, examined the chair with a broken leg, and said, "It was destroyed physically, so it's not a ghost. The fact that someone has been living there recently means he's been planning this for a long time and hasn't left yet."
"Who?" Ron hadn't caught up with Harry's train of thought.
"Who else could know the secret passage to Hogwarts, one of the creators of the Marauder's Map, and dare not show himself in public?" Harry's eyes hardened. "The suspect who may have indirectly murdered my parents, Sirius Black."
Having spoken with Professor Lupin about Sirius's character, Harry knew something about Sirius. But that was over a decade ago, and it was all relayed from someone else; Harry wasn't sure how much of it he could believe.
In his mind, Sirius was not completely convicted, but he was not entirely free of suspicion either.
Ron said fearfully, "Should we go back and call the professor? It seems like the two of us can't subdue him."
Harry was still hesitating when a noise suddenly came from the secret passage behind him. He and Ron quickly drew their wands. A few seconds later, a withered hand reached out, followed by a familiar interjection.
Ron frowned in thought, while Harry also searched his mind for whose voice it was.
The person in the secret passage was far more skilled than the two of them. He nimbly climbed onto the room and ran straight into two magic wands pointed at his neck.
" Professor Lupin?" Harry loosened his grip slightly, and the wand slid from Lupin's neck to his chest.
"I saw you enter the secret passage," Lupin calmly displayed his hands to indicate he was not aggressive, "I wanted to see what you were doing here, and whether you might encounter any danger."
Harry cautiously added, "We suspect Ron's Scabbers got lost here."
He didn't mention Sirius because he wasn't sure of Professor Lupin's current stance. Even though Lupin was his professor, Harry had to be vigilant; if Lupin switched sides, they might pay with their lives.
Unexpectedly, Professor Lupin smiled with relief upon hearing Scabbers, and ignored Harry and Ron as he prepared to push open the door to another room.
"There is indeed a mouse here, but its name isn't Scabbers, and it's missing a finger— Harry, does this remind you of anything?"
"I come to the Shrieking Shack often," Lupin said, turning back to invite. "You know, Harry, I used to be a Werewolf, and the Shrieking Shack was practically built for me. I could just hit the scab on the Whomping Willow and get here unharmed—"
"Good heavens!" Upon hearing this, Ron raised his wand again, still protesting, "Missing a finger? That's Scabbers!"
But Harry gently pressed his wand downwards, explaining, "Don't worry, Harry, the professors all know Professor Lupin is Werewolf, Ron they've already taken care of it."
"You're so noble for not telling anyone my secret, Harry, just like James I know," Lupin with great satisfaction. "Since you're here, why don't you come with me? Maybe that mouse has something to say to you."
Ron had already angrily followed after them. If he saw his Scabbers being abused, even if it was Lupin on the other side, he would definitely draw his wand without hesitation.
Harry had intended to pause and ponder the hidden message behind "a missing finger," but seeing Ron had already followed, he worried that Ron might act impulsively or get into trouble, so he immediately caught up and stopped him. " Ron, stop! We need to calm down!"
It's too late.
The door to the innermost room was open, and Ron immediately saw his own Scabbers. It lay motionless in the cold cage, as if dead. Beside Scabbers, a handsome man was watching it.
The man had curly hair and crossed his legs. He had been staring at Harry with a smile on his face the moment Harry walked into the room. Harry and Ron immediately recognized him as Sirius Black, the wanted man in the newspapers. However, his radiant and energetic appearance was a far cry from his previous crazy and desperate look as a fugitive.
Who is helping him?
Harry immediately pulled out his wand and pointed it at Lupin, while Ron simultaneously pointed it at Sirius. The air seemed to freeze, but the two adults ignored it and even chuckled softly.
"How similar you are, Remus, how similar you are to us back then."
Harry couldn't bear such relief and admiration.
If his parents hadn't died because of him, he should have revealed the truth immediately, instead of calmly playing the role of the riddle teller. His disregard for him and the wand trampled on his burning ambition to avenge his parents, making his painstaking efforts to find the truth seem like a joke.
If his parents died because of him, then his current attitude shows absolutely no remorse. In any case, Harry has a reason to take action.
" Incendio-- "
"Meow!"
Just as Harry was about to unleash the spell, Crookshanks suddenly leaped onto Sirius's chest, and Harry flicked the tip of his staff, burning a hole in the ceiling above him.
"Good heavens, Crookshanks is a Death Eaters!" Ron controlled Lupin's movements while keeping an eye on Harry's side of the battle.
"It's not Death Eaters," Sirius defended a cat. "It tells me about your mouse. The day your mouse chewed through the cage and escaped, it was it that came to tell me. Luckily it arrived in time, otherwise your mouse might have frozen to death in the sewer."
Sirius released Crookshanks, stood up, and walked step by step to Harry, resting his chin on the tip of Harry's wand.
"Just don't kill me, Harry. Torture me however you like. Your parents... I'm to blame. That's why I chose to go to Azkaban. But please don't overlook the real killer."
Sirius pointed at the mouse in the cage, gritting his teeth, and said, "That's it, Pettigrew Peter."
"What Peter? That's my mouse." Ron didn't know who to aim his wand at, and he swung it back and forth, unsure of what to point it at.
"I guess you've already heard," Sirius said, drawing his wand in front of Harry and pointing it at Scabbers in the cage, "There's a kind of magic called Animagus."
A white beam of light pierced into the cage, and Scabbers, who had been playing dead, immediately began to squeak and squeal. Amid Ron's attempts to stop it and Sirius's maniacal laughter, its body gradually swelled up, and its black fur transformed into a filthy suit. The only thing that remained unchanged was its pair of shifty, rat-like eyes.