There are many air-raid shelters in my hometown, most of which were built during the Sino-Soviet split. The slogan at that time was "store more grain and dig deeper tunnels". Many air-raid shelters were left unattended since the mid 70s. When I was a kid, I often played inside them.

  The place we are in now is like an air-raid shelter, with a vaulted ceiling and walls that are only as wide as the span of both arms. The rocks above show many signs of artificial excavation, and as we move forward, water begins to appear underfoot, soon rising above our ankles. It is also here that the path ahead starts to fork.

  Left or right? That sickly seedling ran faster than a dog, the river water mixed with silt, black and murky all over, the footprints under the water can't be distinguished.

  "It's either all the way or nothing at all, we've got to investigate this thoroughly, otherwise let's just withdraw."

  "People with similar fates as us often make similar choices, I believe he must have discovered something."

  "What? That mud-eating guy is really a weirdo."

  Cha Wenbin said, "He did that for a reason. There is a yin energy in this mud. This person is not simple. The knife he's holding, I've seen it once before. It's called Han Yue. Whether you believe it or not, it's said that the knife used by Jing Ke to assassinate the Qin Emperor was precisely that one."

  "Wow, it's really valuable! That's worth a lot of money." In Pangzi's eyes, everything is measured by its monetary value.

  "It's not that it's valuable, but the sword will recognize its master. Since he can pick it up, he must be no ordinary person. To make Dragon Lord take a second look is even more extraordinary."

  I couldn't bear it anymore, and the question that had been bottled up in my heart for a long time finally came out: "What kind of person is Dragon Lord?"

  "The country's people, I don't know how to say it, they are a special kind of existence, with all sorts of characters from the three teachings and nine streams. In this world, there are many such organizations that cannot be exposed to the light of day, some things can only be done by people like them, laws and morals have no hold on them, they are only loyal to their own leader, just like the Military Bureau and Central Bureau during the Nationalist Party era."

  "The United States also has them." Old Gu said: "You may only know about the Federal Bureau of Investigation, which is semi-public. In fact, there are many more hidden departments like this."

  "Are you a secret agent or something?"

  "I'm not saying I am, because I'm not." This is a typical American humorous response, very cool...

  I continued to ask Wen Bin: "Are you also from that organization?"

  He thought for a moment and then shook his head, "I'm not, I don't want to be, not interested. Alright, I think we should go somewhere else, that friend left us a mark." Cha Wenbin pointed at the stone wall on the left side of the passageway and said, "There's a scratch, still very fresh."

  The water is getting deeper and deeper, the deepest part has already started to overflow my chest. I'm fine, this waterproof suit is not bad, but I'm afraid that the low temperature will be harmful to the old man, so I said to him: "Professor, why don't we retreat first? The situation here is unclear, you are a scholar, there's no need to take such a great risk."

  "No, you know Peng Gang, right?" he asked me.

  "You know, all Chinese people know about it. It was reported in newspapers and on TV. That scientist who went missing at Lop Nur two years ago."

  "He is my friend and one of the most respected Chinese scholars I know. If a scientist dies in bed, then his life has been a disappointment."

  I've started to have a deep respect for this fake foreign professor's character, so I had to remind Fatty to take good care of him.

  It wasn't until then that a sour smell began to appear in my nose, just like the kind of gas emitted by stagnant water left in a bucket for too long.

  "The water here smells so bad, it shouldn't be like this since it's supposed to be running water."

  "It's the smell of rot, don't you feel a bit slippery under your feet?" Zhang Wenbin said next, I'd rather he take it back or I didn't hear him say: "Do you see that layer of oil floating on the water surface? Those are corpse oils, we're probably near the burial pit now."

  The pot at home, if not washed clean and boiled water, there will be a layer of colorful things on the surface of the water. At this moment, the waters around us are these things. I am a young man who loves cleanliness, suddenly there is a sour thing in my stomach that is rolling up and down...

  The fatty seemed to be dissatisfied and continued to add fuel to the fire: "Are those hard things underfoot bones?"

  The old man reminded: "So be careful not to step on the bones, after the corpse rots, it will produce ammonia, which is miasma. If you feel a little unwell, don't force yourself."

  The water is getting deeper and deeper, and if you go further forward, you have to rely on swimming. I don't know how many years or months it has been since anyone came here, and what I'm even more worried about is whether there will be a sudden appearance of those biting fish in the water.

  All around was quiet, the spotlights on each of their heads collided here, and only the sound of "gurgling water" came out. I tried to tell myself not to be nervous, but my feet slipped under me, and my body lost its balance and fell backwards, colliding with Old Gu.

  At his age, Gu Lao couldn't withstand my strength, and naturally, he couldn't hold on either. The two of us thrashed about in the water until we both slipped under. I don't know how many mouthfuls of dirty water I swallowed before I managed to struggle back up to the surface. When I finally broke through the water's surface again, only Gu Lao and I were left; Fatso and Cha Wenbin had vanished!

  From falling into the water to getting out of the water, it's only about ten seconds at most, isn't that like seeing a ghost?

  I was just about to look for it when I heard a "thud" sound next to my ear, and a stone almost hit my head.

  "Here!" I heard Pongzi's voice, and looked in the direction, about ten meters away from me, Pongzi's head was facing down, sticking to the water surface, smiling at me.

  I and Gu Lao rushed over there, the water was already above my nose at that time, I had to swim, when we arrived, it turned out that there was a hole in the stone wall on this side. Gu Lao and I also went ashore one after another. Not only is this place really hidden, but about 30 centimeters above the water surface, there is a triangular cone-shaped hole exposed, people have to dive into the water again to enter, and only when you enter will you find that this is a different kind of cave.

  The fat man pointed at the sickly-looking guy squatting on the ground behind him and said to me: "That little brother invited us in."

  "I said angrily: 'Don't care about our lives? I almost drowned! Ah, how did he sneak in?'"

  "The devil knows, if he hadn't beckoned us over, I reckon we wouldn't have noticed. Just now, from what Cha Ye said, this seems to be a heavenly ascension path."

  I only now noticed that this place is a bit different, with stone carvings on both sides. The ones near the entrance are probably always submerged in water and can't be seen clearly. The murals use white and red hues, with simple lines, which would be considered abstract art by modern aesthetic standards. The painting is very long, stretching from where we stand all the way up to the front, with almost no empty space. I vaguely recognize images of horses and carriages, people, and some animal patterns.

  Zha Wenbin asked: "Mr. Gu, you are a researcher, what style is this painting?"

  "The murals in the tomb after Han Dynasty already had colors, and the figures and patterns were also more three-dimensional. By Sui and Tang Dynasties, they reached their peak. The composition of this painting seems to be far beyond Han, even as early as Spring and Autumn or Warring States periods. It is very similar to those paintings found in the Gobi Desert at the end of last century, but it's hard to explain, given the huge gap in time."

  Zha Wenbin also said: "We infer that the tomb below is approximately in the Southern and Northern Song dynasties, logically it should be around that time period here too, how can there be ancient paintings from a distant past?"

  Guo Lao walked forward about three meters, sticking close to the murals, and exclaimed: "Come take a look! This mural depicts scenes from bottom to top, indicating that the painter back then was also walking upwards along this path, just like us." He asked the sickly youth again: "How did you discover this place?"

  "Intuition." This was his first utterance, spoken with his head still hung low, his voice slightly hoarse but very charismatic.

  "Your intuition is remarkable." The old man praised: "The discovery of this painting has great historical value, and it may be possible to push the civilization of Jiangnan forward by two thousand years. This painting depicts the prosperity of a tribe, these animals represent wealth, those people holding weapons are symbols of their military power, and that person. Mr. Gu pointed at a human figure in the mural and said: "This person, you notice, his image is different from others, note that there is a triangle on his head, similar to a hat, he appears most frequently in these murals, should be a person of high status."

  After a while, Old Gu called out again: "Come here, come here, look over here. What is this thing that these people are worshiping?"

  There are six people painted on that picture, the leader is still the guy with a triangle on his head. Their knees were painted as folded lines, crawling towards the ground. What's even stranger is that the object being worshiped in this painting is an ellipse with two short slanted lines at the bottom. Above the ellipse, there is another person whose head also has a triangular object, and his hands are still open.

  I tentatively asked: "Is this a Ding?"

  "Exactly! This is a ding! The person standing on the ding is their leader, this information is too important, so we can shorten the time to before the Western Zhou period at once, this discovery may change history!"