Sherlock and Hilke stopped in their tracks together.
Based on their pace, they had walked about two kilometers in nearly half an hour.
Crossing the entirety of Hogsmeade would not have taken this long, which meant they were no longer within the Hogsmeade area.
Sherlock frowned as he looked at the glowing wand in his hand; the range of light, which had been around five meters before, had now shrunk to two.
The visibility was getting shorter and shorter, and he could be certain this was not an issue with his spell.
Once a Lumos Charm is cast, as long as the Wizard does not interrupt it, its luminosity remains constant.
Therefore, it was impossible for the Lumos Charm to inexplicably weaken; the issue had to be with the surrounding environment.
Hilke cancelled the Lumos Charm on her wand, then placed the wand vertically on the ground, with the tip pointing upward.
"Point me the way."
She said softly, then released her hand from the wand, and it fell straight forward.
"We are heading south."
Ahead, it was still pitch black, as if the path would never end.
Sherlock mentally recalled the map of the surface.
In this area, Hogwarts was to the southeast of Hogsmeade, while the Hogs Head Inn was at the very north of Hogsmeade.
They had been walking south the whole time; this distance certainly meant they had left the Hogsmeade area and entered the Hogwarts grounds.
As for whether they were directly beneath the Quidditch Pitch or the Castle, it was impossible to know.
"We have reached the Hogwarts grounds," Sherlock said, stroking his chin and looking around. "And there is something wrong with this secret passage."
Hilke picked up her wand again.
"This proves we haven't come to the wrong place. Its destination is Hogwarts. The more problematic this place is, the more it proves that it has been here, or is here right now."
Her words made Sherlock instinctively touch the cloth bag in his robe pocket; it was thick and sturdy, which put him a bit more at ease.
"Alright, we've come this far. Can you tell me now if normal magic has any effect on that thing?"
Hilke did not hold back her words this time; she explained in detail.
"Normal magic is useless against it, even the Killing Curse. It cannot be killed, never will be, but it fears the Patronus Charm."
Sherlock raised an eyebrow.
"Sounds a bit like a stronger version of a Dementor."
"You can certainly think of it that way."
Sherlock flexed his wrists and adjusted his robes.
"If it has a weakness, then there's nothing to fear. You might not believe it, but the Patronus Charm just happens to be my speciality." He turned to look at Hilke. "What about you? You're always pulling a long face; can you even cast that spell?"
Hilke ignored him, instead waving her wand to light it up again, and continued walking forward.
Sherlock shrugged, sighing to himself that German Wizards were indeed this boring, then quickened his pace to walk beside her.
They walked for about another twenty minutes.
Not only was the darkness getting darker, with their Lumos Charms eroded to a visibility of less than one meter, but the surrounding temperature was dropping, as if winter had already arrived.
Neither of them was delicate, and they could endure this bit of cold, but the surrounding environment was gradually becoming eerie.
All sound seemed to have vanished; apart from their footsteps on the ground and their faint breathing, there was nothing else.
Even though they were underground, the silence was terrifying.
"Let's chat," Sherlock couldn't help but speak first while walking.
Surprisingly, Hilke did not respond with silence or a refusal.
"Hmm."
"I know you might be used to this kind of silence; I feel like you could probably sit still for an entire day when you're doing divination."
"No one is used to it from the beginning."
"When did you start to know you had a talent for divination? I remember that such talent is usually hereditary."
Hearing Sherlock's question, Hilke paused, but she still answered.
"Seven years old."
"You knew you had a divination talent before even going to magic school? Did you have some kind of prophecy master in your ancestry?"
"I never went to magic school."
Sherlock looked stunned.
"You never went? I thought you were a graduate of Durmstrang. Where did you learn your magic then?"
Hilke wrapped her black robes tighter around herself.
"My mother."
"Family-style magic education? That's quite rare. I remember reading a document stating that after Beauxbatons, the last of the three magic schools to be founded, was established, family-style magic education in Europe completely disappeared. After all, people in one family can't know everything."
When discussing this topic, Sherlock associated it with other things.
"Actually, magic schools have maintained the same status quo since their founding a thousand years ago; I don't see any progress. Wizard education focuses too much on magic skills, while ideological guidance mainly relies on the family. Students' concepts in school are basically like untended vines, growing upward along the mainstream thoughts of the Wizarding World, and inevitably, there are cases where they grow crooked."
"You talk too much."
Hilke responded to his long-winded speech with this.
Sherlock shrugged.
"In this atmosphere, well, I suppose it is a bit more than usual."
The temperature seemed to have dropped to a fixed point, but once accustomed to it, it did not feel particularly unbearable.
It was just getting darker and darker around them.
The visible light from the Lumos Charm had been compressed to less than half a meter; if one stretched out an arm, it was pitch black.
The sound of Sherlock and Hilke's conversation grew lower and lower until both fell silent.
Because they had reached the end and arrived in front of a door.
They placed their wands in front of the door together and saw that it was a plain, unadorned wooden door.
The door was empty, with nothing on it; it was as simple as could be.
But Sherlock did not reach out to push it directly; instead, he tentatively cast an Alohomora on it.
The wooden door did not react at all.
Even if it was not locked, a normal door would open on its own under the influence of an Alohomora; this door was clearly not as simple as it looked on the surface.
Sherlock turned his gaze to Hilke.
"In the information you received, was this door crafted by Goblins?"
"No." The lower half of Hilke's face that was exposed looked inexplicably pale. "They didn't tell me that."
Sherlock frowned. He extended his wand, wanting to tap the door surface with the tip to check for anything special.
However, before he could even extend his hand, Hilke's voice suddenly rang out.
"Don't touch it!"
Sherlock stopped his hand and looked at Hilke, who had stopped him. Her gaze, hidden under her hood, was directed toward the area directly above the door.
Her lips were devoid of colour, as if she had seen something unacceptable.
Sherlock followed her gaze. At the very edge of where the light could reach, on the stone wall above the wooden door, hung a withered, yellow piece of straw.
It was clearly hung there intentionally.
Tied with a rough hemp rope, it dangled from the pitch-black darkness, hanging above the door.
The bizarre feeling was as if someone was using the hemp rope as a fishing line, the straw as a fishing hook, and the bait to lure someone in... was the wooden door right in front of them!
Sherlock noticed that Hilke's state was off, and he asked solemnly.
"What's wrong?"
"It knows someone will find this place." Hilke's voice remained cold, but her tone seemed to be trembling slightly.
"So it deliberately left this thing behind, waiting—waiting for us to find it here."
Sherlock looked at the straw hanging by the hemp rope. From the outside, it looked exactly like the two pieces of straw they had picked up on the hill and in the backyard of the Hogs Head Inn; it was completely ordinary.
But this piece of straw was definitely not that simple.
"So?"
"To get inside, you have to pass through this door." Hilke's tone became noticeably chaotic. "Opening it is easy; all magic spells have no effect, but you just need to push it with your hand. However, when pushing the door, that person will have to experience their greatest fear. If they can endure it, the door can be pushed open."
She did not say what would happen if they could not endure it, and Sherlock did not ask.
Because even without saying it, everyone would understand the answer.
"Let's leave first. There must be more than one way to open this door; we can go find others to help."
Sherlock said calmly.
But Hilke shook her head.
"There is only this one. I have guarded it for five years and know its methods. It isn't strong, but in its domain, no one can override its authority."
"Maybe it isn't inside the door at all; this door is just a lure. We can look for other clues and think of another way."
Sherlock still did not want to take the risk.
Whether it was him or Hilke, he felt there was no need to take the risk.
But Hilke's thoughts were clearly different from his.
"You must hold me down later."
When she said this, she actually calmed down.
Sherlock's brows furrowed together.
"I don't think such a risk is worth it."
"It was I who failed to keep an eye on it, so I must catch it and bring it back." Hilke said softly.
She handed her wand to Sherlock, walked to the door, and took a deep breath.
"If I try to do anything self-destructive, hold me down. Also, no matter what unexpected thing happens, do not speak."
Sherlock held the two wands in his hand. Seeing her stubbornness, he was silent for a moment, then slowly nodded.
"I understand."
After hearing his affirmative reply, Hilke extended her pale, slender hand and placed it on the door surface.