The next day, Mo Zi quietly left the mansion with Zan Jin.

She had to be quiet—as Prime Minister Yuan’s wife, whenever she went out now, the head steward would arrange for at least a hundred guards to escort her, fearing they might encounter spies or assassins along the way and lose her life, unable to answer to Prime Minister Yuan.

“It’s been so long since just the two of us went out alone.” Dressed in servant’s clothes, Mo Zi openly mixed through the main gate with Zan Jin, wearing black boots and a cap, her expression completely carefree.

Zan Jin felt it necessary to clarify, “Lanyi is here too.”

Mo Zi looked left and right but didn’t see any blue clothing. “Where is he hiding? Why can I never spot him?”

Zan Jin pointed to the rooftop. “If we’re going far, I’ll leave secret marks and he’ll follow behind.” Of course, it was impossible to hide all the way. “Although this entire area is within the Song army’s defensive line, it’s still better to be careful.”

Mo Zi nodded. “I’ll leave security matters to you.”

Zan Jin replied, “If you’re truly leaving it to me, it would be best not to leave Hengcheng at all.”

“The weather is so lovely—perfect for an outing. I bet there are definitely many young people meeting up in the suburbs to enjoy the flowers.” Not listening, she walked her own path.

Zan Jin smiled helplessly, knowing that once she made up her mind, it was very difficult for others to dissuade her.

Taking the official road, Mo Zi was in no hurry. What had originally been widespread desolation had changed greatly in just a few months. Nearby were tender yellow and fresh green rice paddies, and in the distance cooking smoke rose from farmsteads. Though it would still take a long time to restore the former prosperity, the spring vitality was delightfully flourishing.

They set out early in the morning and reached Song County at the third watch. Without looking for an inn, they headed straight for the pier. On this day, a full moon hung in the sky, casting silvery light for a thousand miles, illuminating the mountain ranges in undulating shadows.

Mo Zi pulled out the woodblock print from her bosom, gently rubbing it in her hand, then finally fixed her gaze on the small mountain before her. That’s right—this was the place.

“Zan Jin, tell me—how are all parents so incredibly capable, as if they each had three heads and six arms?” She felt admiration for her father and her father’s father’s father flowing like surging river waters. “Who would have thought the entrance to the treasure mountain would be right at our own doorstep?”

Zan Jin was shocked and astonished. “Brother Mo.”

The place where Mo Zi stood was in front of the forest where the Min Fifth couple’s residence had been burned down. What she faced was a small mountain. Calling it a small mountain was even a bit of a stretch—more like a small hill.

“This hill has a name. Because it’s so small and insignificant, the Yuling maps and county records don’t specifically note it. But it’s on the ancient Tang dynasty atlas and geography texts.” She spoke.

“Mingshan?” Without Mo Zi saying so, Zan Jin wouldn’t have considered it a mountain at all.

Mo Zi shook her head. “Fengming Mountain.”

“Fengming Mountain?” Zan Jin didn’t understand. “But Dou Lu—”

“Either she didn’t remember accurately, or my mother deliberately misdirected—the real location is hidden in the first line of the four-line riddle.” A phoenix comes to Mingshan. Fengming Mountain.

“But—this mountain has no cave.” No matter how small a mountain, there should at least be some sand and stone cave, right?

“There is a cave. However, we can’t see it from here. Come on, let’s go up and look.” Mo Zi walked toward the hill.

Even in the dark night, they could see their surroundings clearly with just the firelight. There were no trees on the hill, and the ground was covered with soft grass. This hill looked as if someone had dug up earth with nowhere to put it and casually piled it up. The hilltop was a circle where a dozen or so children could stand and play games.

Perhaps they got it wrong. Zan Jin thought this but didn’t say it, because Mo Zi always acted with certainty.

“Just as I thought.” After Mo Zi said this, she led her horse down the slope.

Zan Jin couldn’t see what was “just as she thought,” but his virtue was asking little and doing much, so he followed without question.

Below the hill was a small pond that seemed to have been used for fish farming before, with a few old floats still there. Under the moonlight, ripples spread across the water’s surface as fish blew bubbles.

“Guess what this pond is called.” Mo Zi’s mood hadn’t been this leisurely in a long time, as if visiting famous scenic spots, leaving footprints from a stroll.

“Isn’t it a fish pond?” Zan Jin had no imagination for anything outside of martial arts manuals.

“Baojing Pool.” Mo Zi laughed lightly, her voice as pleasing as bells. “Interesting, right? A small mound of earth given a mountain name, a small pond given a pool name—the wisdom of our predecessors, admired by later generations.”

Zan Jin did find it interesting.

“Not until Dou Lu remembered all four lines of the riddle did I finally determine the location of the Sand and Stone Cave.” She removed the bundle from the horse’s back and took out an olive-shaped drum skin bag, then stripped off her cloth clothes and strapped it onto her sharkskin suit.

Zan Jin knew she was going to dive. “I’m going too.” His swimming ability had improved greatly under that stinking fish’s training.

“Of course you’re coming with me. I’m afraid water monsters might pop out.” She’d brought him along precisely to pull him into the water. She handed over the sharkskin suit and drum skin bag, instructing, “You need to wear the flippers too.” The pond was shallow, but the secret was deep—they had to be prepared for any eventuality.

“However, if we’re going underwater, it would be better to wait until daytime. The pond is murky—I’m afraid we won’t be able to see clearly underwater.” Zan Jin considered this.

“Isn’t the last line ‘heart and eyes distinguish the precious mirror’ quite mysterious?” Mo Zi had considered even more than Zan Jin. “Maybe the darker the better. Remember, stay close to me once we’re down there.”

Zan Jin said no more. He went to a secluded spot to change clothes, did his warm-up exercises, fitted a soft leather mask over his mouth, and jumped into the pond.

The spring water was still cold. Mo Zi, wearing the sharkskin suit, shivered slightly, then flipped over and dove into the water. The equipment hanging from the skin bag helped her sink. Opening her eyes was futile—the moonlight only penetrated the shallowest layer of water. Apart from Zan Jin’s blurry figure beside her and the fish they’d startled, beyond a few feet it was pitch black. She pulled out a compass and found her direction by the cold blue light of a luminous pearl. The four lines contained no directional words, but the ancients honored the southeast, and if dividing the precious mirror, there might be a mechanism. Mechanisms had to be built against walls or the bottom. This pond wasn’t large, and the air in the drum skin bag could supply about fifteen minutes of breathing—they could search slowly.

She signaled for Zan Jin to follow and swam south. After swimming about five or six meters, she suddenly discovered the compass producing a strange change. It had been pointing steadily at the south character, but now it trembled slightly toward the southwest. She almost immediately understood this was because the compass was sensing another magnetic field. Without hesitation, she pulled Zan Jin and changed direction until the needle firmly pointed west and her hand could touch the mud wall.

Mo Zi scraped away a chunk of earth, then had Zan Jin knock it with his fist. Before long, the wall surface revealed a smooth patch that even Zan Jin’s martial skills couldn’t shake in the slightest. Instead of being anxious, she smiled—this should be the right place. After groping around for a while, she roughly confirmed this entrance was a circle with a diameter of one meter.

At this moment, Zan Jin pulled her—he seemed to have discovered something.

It turned out that not far from the circular wall was a protruding stone about the size of a palm. Zan Jin pushed hard to the side, and the stone moved. Under the dim glow of Mo Zi’s compass, it revealed a bronze mirror. In the center of the bronze mirror was a small dark hole.

Mo Zi hastily pulled out a pearl from her bosom and, while Zan Jin’s eyes widened hugely, inserted it into that hole.

At first, there was no movement at all.

Just as Mo Zi felt the oxygen was nearly depleted and pointed upward to Zan Jin, signaling they should surface first, suddenly a surge of water rushed, and the circular wall shifted.

The precious mirror divided!

Mo Zi’s acuity in water was very high. Sensing that the force of the water surge wasn’t great, she knew this opening was designed to go upward, and there was already water inside the cave, mostly level with the pond. This design could also prevent the pond’s waterline from dropping and the water surface from fluctuating.

After thinking this through, she swam directly into the cave. Looking inside, it was indeed an ascending cylindrical passage. Swimming upward another seven or eight meters, she burst through the water’s surface and breathed in cold, damp air. Using both hands and feet, she leaped up, pulled out a fire starter from the pouch hanging below the skin bag to light a torch, then wiped the sharkskin suit with a dry cloth and put on a green shirt over it. Her movements were nimble and seamless.

After Zan Jin surfaced, he stared at the narrow passage overhead with infinite wonder.

Mo Zi looked around, found the activation mechanism, and retrieved the water-purifying pearl she’d placed earlier.

The underwater stone wall sealed shut again.

“Aren’t the water-purifying pearls a map? How can they open a stone door?” Zan Jin had questions about everything before his eyes.

“Among these ten pearls, one wasn’t made by Min Zhen but by Min Zhen’s father, and it’s the only Guanyin image without willow branches. The real key is this one, having nothing to do with the woodblock print.” When the ten pearls couldn’t be arranged correctly no matter what, Mo Zi made a bold deduction. “The nine water-purifying pearls Min Zhen made, if arranged according to the number of leaves on the Guanyin’s willow branches, form exactly a three-by-three arrangement. The folds on the Guanyin’s Buddhist robes—I drew them out and they form a maze diagram. In this maze, only one path leads to the treasure location.”

“Brother Mo is truly amazing.” These secrets one after another—she’d cracked them all. Zan Jin admired her tremendously.

“Whether I’m amazing or not, we’ll know after we look.” Mo Zi shouldered the pack.

“Haven’t you already figured it out?” Zan Jin was a bit confused.

“So far, all my guesses have been correct. Whether this good luck can persist to the end—I wouldn’t dare say.” She’d also brought the woodblock print. As the saying goes, it’s better to be prepared.

Zan Jin grinned. “Brother Mo will definitely get ten out of ten guesses right.”

Mo Zi patted his shoulder. “Let’s hope so, otherwise you and I would be in trouble—in here, calling to heaven won’t be answered, calling to earth will get no response.”

“I’m not afraid.” How bold Zan Jin was.

The two walked along an upward slope in the corridor, then along a downward slope, and simultaneously said, “We’re here.”

Because there was a breeze.

“There’s actually no door?” Zan Jin said casually.

Mo Zi thought this way: “The most secret thing about a treasure is its location. Once you’ve entered the entrance, creating the same obstacles again would be pointless.” When she finished speaking, she could actually hear an echo.

Zan Jin stepped into the darkness first. The torch swayed and—whoosh—he suddenly slid down.

Mo Zi was greatly alarmed and reached out to grab Zan Jin, but only touched the corner of his clothing.

“Zan Jin!” She shouted while illuminating with the fire, only then discovering that the original wooden ladder steps had each tilted into slanted boards, forming a slide.

“I’m fine, Brother Mo, just slide down.” Zan Jin said from below.

Mo Zi carefully sat down, puzzled—if this was a mechanism, it was rather comical. A children’s playground? The thought made her laugh at herself.

When her feet touched the ground, Zan Jin had already found the fire basins on the wall. After lighting them all, he looked back and his mouth couldn’t quite close. “What a huge cave.”

“This is the real Sand and Stone Cave.” Mo Zi also widened her eyes.

Layer upon layer, like clouds in the sky, like water on the ground, sand-colored rocks extended everywhere, in varying depths. Some of the thin flake-like ones, under the light, faintly revealed milky white jade cores.

Before even walking deep inside, the treasures were already before their eyes.