Karl's words hung in the air for half a second, but no one responded.

Chen Hao held the toothpick to his lips, Susan paused with her pen, and Nana looked up from the terminal, three pairs of eyes fixed on him.

"It turned around?" Chen Hao put a toothpick in his mouth. "Are you sure you're not mistaken? That thing doesn't have a brain."

“But it moved,” Carl insisted. “I saw it with my own eyes. The sampling pool lights were off, and it suddenly tilted its head toward the camera.”

Susan closed her notebook: "It's normal for organisms to adjust their posture in a closed environment."

“But it had its back to us the whole time,” Carl said. “It was like… it knew we were watching.”

The air went still for a moment.

Chen Hao burst out laughing: "Are you afraid it'll crawl out in the middle of the night to cook hot pot as revenge on us?"

No one laughed.

He composed himself, scratched the back of his head, and said, "Alright, how about we check the neurological responses again tomorrow?"

“Why don’t we investigate the ruins first?” Nana said. “Based on the distribution of hot zones and the direction of the mineral veins, there is a 73% probability that the cave system detected in Chapter 654 has artificial structures.”

"Looking for ruins?" Chen Hao perked up. "Is there anything to eat?"

"uncertain."

"Is there a kitchen? People in ancient times had to cook, right?"

“The logic doesn’t hold up.” Susan shook her head. “We currently have no coordinates, nor any evidence to prove that there are any remnants of civilization there.”

“But there are clues.” Nana pulled up the map. “The location where S-749 was last collected was near an unmarked area of ​​magnetic field disturbance, and that area overlaps with the outlines of three suspected buildings. Combined with Chen Hao’s resource back-inference method—high concentration of crystal-filtering bacteria, luminescent algae aggregation, and abnormal metal deposition—they all point to the same fan-shaped area.”

"So, can we go take a look?" Chen Hao sat up straight.

"Assuming the equipment can withstand it," Susan cautioned. "The water pressure there is higher, and the corrosiveness is stronger. Last time, the edges of my diving suit were all white when I came back."

"Then let's upgrade." Chen Hao slammed his hand on the table and stood up. "Anyway, we've finished eating and don't need to take a shower. Let's start now."

When the laboratory lights came on, the residue on the transport container walls glowed faintly.

Susan gently scraped off a small piece of the sticky substance with a scraper: "This stuff sticks very well; you can't wipe it off."

“The composition analysis is complete.” Nana took the sample. “It contains 60% silicon polymer and is mixed with nano-sized titanium-tungsten alloy particles, which have pressure response characteristics. In a simulated 3,000-meter water depth environment, after micro-cracks appeared on the coating surface, it completed self-filling within 30 seconds.”

"Can it be used on diving suits?"

“It’s theoretically feasible.” Nana nodded. “After spraying, a dense protective layer is formed, which increases the pressure resistance by about 40%.”

“Let’s get started.” Chen Hao rolled up his sleeves. “I’ll mix the ingredients.”

They used a centrifuge to extract the active ingredients and mixed them with a thinner to create a spray coating. Carl was responsible for adjusting the spray gun pressure, Susan controlled the ambient humidity, and Nana monitored the molecular adhesion in real time.

When the first test suit was placed into the hyperbaric chamber, Chen Hao stood close to the observation window.

"If it explodes, at least we can see where the debris is flying."

"It won't explode," Nana said.

Ten minutes later, the alarm sounded.

"Did it leak?" Susan frowned.

“It’s the coating that’s deforming.” Nana zoomed in on the image. “The outer layer is contracting under pressure, and the internal structure is reorganizing. Once the pressure reaches a critical value, the crack closure speed accelerates.”

The data has stabilized.

“He’s alive again,” Carl muttered.

“It’s not alive,” Nana corrected. “It’s the activation of an intelligent response mechanism. Similar to muscle contraction when it gets cold, but driven by the material’s own properties.”

"Who cares how it moves?" Chen Hao waved his hand. "As long as we don't lose air on the seabed, it's fine."

Four hours later, all four new diving suits were processed. The outer shells had a matte gray-blue hue, like stones shrouded in a thin mist.

"It looks a bit ugly," Chen Hao said, touching his shirt. "It's like wearing a trash can."

“Defense is the priority.” Susan checked the sealing strip. “It’s two kilograms heavier than before, but mobility is not affected.”

"As long as I can run, that's fine." Chen Hao shook his arm. "If we run into that big monster, I'll have to run even faster."

Half an hour before departure, the oxygen circulation system suddenly alarmed.

A continuously flashing red light indicates a main module malfunction.

"Didn't it just work fine?" Chen Hao stared at the screen. "Could it be that it knew it was going to take a risk and got scared into shutting down?"

Carl disassembled the panel and reached inside to feel it: "The sensor is damp. It's probably because water got in during last night's rinsing, causing the signal to drift."

He unplugged the connector, dried it with a cloth, and plugged it back in tightly.

The alarm has been turned off.

"It was a false alarm," he said.

“Even machines get nervous.” Chen Hao patted the machine. “I understand, I get nervous too.”

The submersible slowly opened its interface, and seawater rushed into the channel.

The four people entered the cabin one by one and closed the sealed door.

Chen Hao sat in the passenger seat, watching the water ahead gradually darken.

"If only we could find an ancient kitchen this time," he said. "Maybe we could even dig up a cookbook."

“More likely we’ll find a bunch of rocks.” Susan checked her toolbox.

“You can make soup from stones too,” he retorted. “Just smash them up, add water, and boil them with a little salt; that’s a flavor enhancer.”

Nana activated the navigation system and set the route.

The thrusters hummed softly as the submersible detached from the base and began to sink.

Outside the porthole, the light quickly disappeared, leaving only the faint glow of the instrument panel reflecting on my face.

"Depth 1200 meters, steady descent." Carl gripped the control stick. "Ahead is a canyon area. Expected arrival time: two hours to the target area."

"Remember to drive slowly." Chen Hao stared at the sonar screen. "If I see something that looks like a pot, I need to brake in advance."

“All you ever look at is food,” Susan said.

“I look at it practically,” he retorted. “If it’s edible, it means the environment is safe; if it’s inedible, it’s dangerous.”

Nana suddenly spoke up: "A slight vibration wave has been detected, coming from the left front."

"Earthquake?" Susan looked up.

“No.” Nana tuned in. “The frequency is unstable, it’s like… metal friction.”

"Rusty iron sheets on the seabed?" Chen Hao leaned closer to the screen. "Maybe it's an ancient refrigerator."

“The probability is less than five percent,” Nana said. “But the magnetic field readings in that area are abnormal, interfering with some of the scanning functions.”

“That means something’s blocking it,” Chen Hao grinned. “The more it’s blocked, the harder it gets.”

They continued on their way.

The coating shines slightly in low-pressure environments, like the writing slowly showing through damp paper.

Susan noticed this and reached out to touch the bulkhead.

"The temperature is a bit low."

“That’s normal,” Nana replied. “With increased depth, the external water temperature drops. The new coating has lower thermal conductivity, improving internal insulation by 18 percent.”

"It sounds warmer than my down jacket."

"Your down jacket has not undergone a 3,000-meter water pressure test."

"But it can fit two of me."

The conversation paused for a few minutes.

The sonar image was stable, with only occasional flashes of clutter.

Suddenly, a soft sound came from the lower right.

It felt like a fingernail scraping against glass.

Chen Hao turned to look at the side window.

Who's knocking on the window?

No one answered.

Carl glanced at the monitor: "No external contact, it must be that the rock strata have loosened."

"Does the rock strata speak at certain times?" Chen Hao stared at the pitch-black outside. "That last one was pretty accurate."

“There are often geological noises in the deep sea.” Susan flipped through the recorder. “Don’t over-interpret it.”

“I’m not interpreting it,” Chen Hao said in a low voice, “I just feel… it knows we’re here.”

“Who?” Carl asked.

“That place,” he said, gazing ahead, “that place no one should go.”

Nana's calm voice rang out: "We are still 170 minutes away from the target area. We recommend keeping communication open and avoiding acting alone."

“I didn’t intend to go alone.” Chen Hao leaned back in his chair. “But I’m warning you, if we really discover some ancient restaurant, I’ll be the first to rush in.”

"That is, the door doesn't collapse," Carl said.

"Even if it collapses, I'll crawl in."

They watched in silence as the darkness deepened ahead.

The instrument ticked, maintaining its rhythm.

Suddenly, the sonar picked up a regular signal.

Intermittent, but repetitive.

“This isn’t a natural wave.” Nana immediately locked onto the frequency. “It’s repeated eight times at 3.7-second intervals, then it stops.”

"Morse code?" Chen Hao's eyes widened.

“It doesn’t look like it.” Susan frowned. “There’s no corresponding pattern.”

“It’s not animal vocalizations either,” Carl added. “It’s too synchronized.”

Nana began replaying the data stream.

Just then, the submersible trembled slightly.

It wasn't a collision, but more like a kind of resonance.

Chen Hao felt a tightness in his chest, as if an invisible hand had pressed down on him.

He looked down at the instrument panel.

Everything is normal.

But he raised his hand and touched his chest, slowing his breathing.

"Just now……"

He hadn't finished speaking.

A new notification popped up on Nana's terminal.

[External coating feedback: Microparticle adsorption was detected in the midsection of the starboard side]

[Source unknown]

[The trajectory of movement is opposite to the direction of the submersible's travel.]