"This is the mansion."
"This is… it looks like an ordinary mansion to me."
Celestine led Rest to a mansion located a short distance away from the clock tower.
It was a two-story building with a yard no bigger than a cat's forehead, surrounded by an iron fence to keep outsiders out.
For a property supposedly owned by a woman who had once ruled the kingdom, it was remarkably modest — more on the scale of a moderately wealthy merchant's residence.
"That's precisely why no one noticed it until now, one could say. The ownership of this mansion is registered under 'Sanada Shoko,' but the caretaker on paper was a different person. Of course… that person merely lent their name and has apparently never even set foot inside."
"You mentioned there were magical mechanisms in place, but… we can't get inside?"
"Getting over the fence is doable by any means. The difficult part is entering the building."
Celestine opened the gate in the iron fence and stepped onto the grounds. Rest followed after her.
The yard was minimally maintained — weeds had been cut, at least — but it was a dreary sight, devoid of flowers or any decorative plants.
And yet… the front door of the mansion was absurdly grand. A heavy, imposing black door stood before them like a barrier.
"This is the mechanism door I mentioned."
Celestine pointed at the door and explained.
"Above the doorknob, there's a panel with numbers written on it. You're supposed to press them in the correct sequence to unlock the door… but since neither the sequence nor the number of digits is known, no one has been able to open it."
"What happens if you just press them randomly?"
"Apparently the investigators tried that, but when the wrong panel is pressed, a lightning magic spell is cast. The lightning isn't lethal, but it's powerful enough to knock you unconscious."
"Lightning…"
"After several rounds of passing out, they managed to determine that the first panel is '1' and the next is '2.' Beyond that, neither the body nor the mind of the investigator could hold out, so the inquiry couldn't continue."
"…………"
One method for cracking this kind of numeric password is to simply try every possible combination of digits.
The panels displayed numbers from '0' to '9.' If the password was two digits, then trying a hundred combinations would do. Three digits meant a thousand. Eventually, you'd hit the right one.
(But… I have no idea how many digits this password is. If it were ten digits, that'd be ten to the power of ten… a billion combinations. Yeah, that's not happening.)
Even without the threat of getting electrocuted, I wouldn't want to try that.
The investigators who came here before must have brute-forced it carelessly… They'd have been shocked unconscious dozens of times before they even landed on the first two digits, '12.' "Hmm… There's something engraved on the panel. It's too faded to read, though…?"
"Yes, that was reported by the investigators as well. They've already managed to decipher the text."
Celestine held out a sheet of paper.
"Parts of it are missing, so it's difficult to read, but based on their decryption, they believe this is roughly what it said."
"Let me see…"
Rest took the paper and traced his eyes over the short passage written there.
"A sailor's ship, Clark the berry."
"…………"
"We don't know what 'a sailor's ship' means, and we have no idea who these people called Clark and Berry are. We're currently cross-referencing associates of Her Majesty the queen dowager to see if anyone by those names turns up, but…"
"No… I don't think we need to look into it. I just had a flash of inspiration."
"Hm?"
"Let's see… First it was 1, 2, and then…"
Rest began punching in the numbers that had come to him.
It was quite a long string of digits, but he knew immediately which number to press next.
Fortunately, Rest had been a science major in his past life. He still remembered the mnemonic tricks they'd taught in math class.
Once he finished entering all the numbers, there was a sharp click as the lock sprang open.
"It's open."
"No way... How on earth did you figure it out?"
Celestine gasped in surprise, covering her mouth with her hand.
Rest agonized over how to explain it before deciding to come up with some convenient excuse instead.