The next day, Laifu and I stayed up all night to show Ye a crucial discovery.

Back in the 1970s, the school maps showed something interesting. The school's air-raid shelter seemed to connect with an unknown space underground.

And this large unknown space was right beneath the old stone monument!

Ye immediately remembered Grandma Hua mentioning that "Government Ghosts haven't departed this land," could it mean there was indeed an issue underground?

"Where is the school's air-raid command center located? Isn't it marked?" Laifu asked Ye.

"Maybe we can follow the drainage tunnels to check it out and see for ourselves?"

The entrance to the air-raid shelter was located behind the sports equipment room in a small cement-built house.

Laifu kicked down a few rusty railings, and we crawled inside.

We walked down dozens of meters, passing through a heavy metal door designed for air-raid defense, carefully exploring.

The deeper we went, the louder and closer the low humming sound became.

Following the sound, we found a machine room where the humming was coming from a ventilation fan in operation, ensuring the underground air wasn't stale.

Ye randomly pulled a lever on a distribution box, and surprisingly, all the overhead lights turned on, showing that the air-raid shelter's electrical system was connected to the school's grid.

The blueprint indicated that the unknown space was indeed connected here.

"Look!" Laifu pointed to a spot on the left side of the wall that seemed to have a human handprint.

Ye pushed hard on the spot where the handprint was, and a secret door appeared in the wall.

Upon entering, we discovered a completely otherworldly space—it looked like a laboratory.

Several desks were equipped with microscopes and test tubes, and there were some items whose purposes we couldn't discern.

The laboratory connected to several other rooms, resembling prison cells, some of which had shelves lined with bottles and jars.

Due to the dim lighting, Ye walked a few steps further using his flashlight, revealing the contents of the jars, which made his hair stand on end.

There were human organs immersed in those jars!

Though Ye had seen human specimens in natural history museums before and found them not frightening, their appearance in the school's underground made it extremely eerie!

Through one of the glass jars, Ye saw Laifu's distorted face.

"Look quickly!"

Laifu shouted to wake the stunned Ye, holding up a paper with a few vaguely legible traditional Chinese characters spelling out "North China Epidemic Prevention and Water Supply Unit."

"Epidemic Prevention and Water Supply..."

"Damn! It’s the Japanese biological warfare unit!" We both exclaimed almost simultaneously, realizing those weren't traditional Chinese characters, but Japanese Kanji!

As soon as we finished exclaiming, the jars on the shelves suddenly started shaking, as though the organs inside had come to life.

"Ghosts! Damn!" Ye and Laifu both got up to run, but ended up bumping into each other.

When we looked back, the jars seemed motionless as if nothing had happened.

"It's nothing, we probably just saw it wrong. This kind of environment can easily cause hallucinations,"

After collecting ourselves, we continued further in. The innermost room was set up peculiarly, unlike any other laboratory.

There was an arched iron door on the wall, with black scorch marks around it, resembling a fireplace.

The room was piled with human bones, several skulls in the center with hollow eye sockets seeming to speak of tragic past events.

"Laifu, look, this place seems to have been a slaughterhouse where the Japanese killed the locals,"

"Why would they just throw the bones around after killing people?"

"Maybe they were conducting human experiments?"

"No wonder this place under the stone monument feels haunted."

After carefully checking the location with Laifu, we confirmed that this unknown area was indeed a large laboratory.

Storing away the map, we sat down to rest and drink some water.

"What should we do now?"

"Shall we go out and report this directly to the police?"

"No need to report; the police already know about this place!"

Suddenly, a thick, elderly voice echoed from the entrance, nearly causing Ye to drop his water bottle.

Shining the flashlight towards the source, a shadowy figure stood there.

Upon closer inspection, it turned out to be the old principal!