Rainwater trickled down his trouser legs, dripping onto the rim of the sampling bottle, like a free distillation process for the substance. Chen Hao didn't move, his eyes fixed on the ring of blue light on the water's surface—it had flashed briefly, but now he was pretending nothing had happened.

"Nana," he said in a low voice, "is your waveform still alive?"

"The vibration frequency is stable at seventy-two times per minute." The voice in the headphones was flat, "94% synchronization rate with the nematode swarm in area b."

"So," he slowly pulled the PVC rod back a little, "what I'm holding now isn't a sampling tool, but a jump rope? And a bunch of bugs below are taking turns swinging the rope?"

"In theory, bioelectrical signals can be conducted through conductors," she said. "I recommend avoiding contact with metal."

"I'd like to," he said with a wry smile, "but the bottle is already contaminated. Letting go now would be a waste of time."

The green film on the water's surface rippled slightly, like breathing. He held his breath and gave the rod a gentle shake. The bottle opening brushed against the floating layer, and a small wisp of flocculent material drifted into the bottle.

Almost simultaneously, the entire pole jolted violently.

It wasn't a slight tremor, but a rhythmic spasm that shot straight up from the ground, as if someone was gripping the other end and wrestling with him.

He almost let go.

“One-eight-second interval,” Nana suddenly said. “The next signal dip will occur in 0.3 seconds.”

He gritted his teeth and, seizing the brief pause in the vibration, yanked the rope sharply, lifting the bottle upwards. The bottle had barely left the water when the vibration resumed, this time more intense, striking twice in quick succession, like Morse code.

"It won't let me leave?" he cursed as he backed away. "Does harvesting algae require approval?"

He slipped, and mud mixed with gravel rolled down the slope. He stumbled a couple of steps before regaining his balance. Looking back, he saw that the sampling bottle was still in his hand, though the cap was a little loose.

“There is a 62% chance that the seal will be compromised,” Nana warned. “Active ingredients may leak.”

"Then let's run faster." He tightened the cap and put it in his pocket. "Anyway, I'm not some valuable piece of equipment, so I won't have to pay for it if it gets damaged."

When he returned to the front hall, his clothes were so wet he could wring out half a cup of water. He placed the bottle on the counter, his fingers still trembling.

It wasn't from being scared, it was from numbness.

His fingertips felt a persistent, stinging itch, like after a mosquito bite. He shook his hand, but it didn't help.

“The sample has been registered.” Nana took the bottle, and the robotic arm switched to the cryogenic chamber process. “Preliminary spectral analysis shows that it contains a complex of flavonoid polymers and an unknown protein, and the structural characteristics are consistent with the reverse transcriptase inhibitor model.”

"It sounds like it can cure diseases." He leaned against the wall, panting. "The problem is, how do we know it really works? We can't just let the chickens get sick again to test its effectiveness, can we?"

"The viral replication blocking rate can be tested in an in vitro simulated environment," she said. "It takes four hours."

“Okay.” He nodded. “Then you go ahead with your work, I’ll check how much filter media we have left.”

He froze when he pulled the cabinet open halfway.

The bottom layer originally contained several rolls of spare activated carbon, but now only half a roll remained. Scattered nearby were several pieces of cut PVC pipe—the very materials he had taken that morning.

“I didn’t touch anything else,” he muttered. “I just took a tube to make a fishing rod-style sampler, shouldn’t the rest still be there?”

“There has been a slight abnormality in the underground pipeline system recently,” Nana said. “Some branch lines are experiencing reverse siphoning, which may lead to dampness and contamination in the material area.”

"So the pipe got soaked?" He pulled out a section to examine it, and the surface was indeed a bit sticky. "Wait... this isn't water stains."

He leaned closer and smelled it; there was a faint scent of rust mixed with grass.

"This is... algal secretions?"

“The probability is 79 percent,” she said. “Furthermore, the substance has weak conductivity, which may interfere with sensor readings.”

He looked up abruptly: "You mean, that thing in the pool just now not only shook, but also crawled out?"

“There is no direct evidence at present.” She paused, “but from last night to this morning, the drainage ditch on the west side of the base was recorded to have been opened three times without human intervention, and the valves were rotated at 15 degrees in each case.”

"Fifteen degrees?" He frowned. "Who's so bored as to turn on the valve in the middle of the night?"

“The system logs did not identify the source of the operation,” she said. “It was not triggered in either manual or automatic mode.”

The room was silent for a few seconds.

He looked down at his still numb fingers and suddenly smiled: "I get it. It holds a grudge."

"What?"

“I said,” he patted his pants and stood up, “we thought we were going to collect its algae, but actually it was collecting our intelligence. Once it figured out the route, it started making small moves. First, it would shake the pole as a warning, and when it found I didn’t listen, it would secretly open the door and release water to test our reaction speed.”

“The logic chain is established,” she said. “It is recommended to strengthen water source isolation measures.”

“We have to add more.” He walked to the workbench. “But the most important thing now is to finish making this bottle of ‘ink.’ The chicken still has a fever and can’t wait much longer.”

He found an old centrifuge and plugged it in. The machine hummed a few times, and the screen lit up with a red light.

"Lack of coolant," Nana reported after scanning. "The last rainstorm caused a slight leak in the storage tank, and the remaining amount is insufficient to support the entire extraction process."

"That rain again caused all this trouble," he sighed. "Alright, what's the temporary alternative?"

“Deep well water can be used for pre-cooling, but impurities need to be filtered out.”

Where's the filter?

"Standard models are out of stock; composite filter media can be used for assembly."

He opened another cabinet and pulled out a bunch of parts: two carbon rods, a honeycomb ceramic plate, and half a nanofilm.

"Let's put it together." He picked up the screwdriver. "It's not like this is the first time I've repaired broken equipment."

The two teamed up and began assembling. He was responsible for welding the joints, while she adjusted the flow channel pressure. During the process, he reached for the tools several times, only to find that the numbness in his fingertips was getting worse, making his movements a little slower.

“The efficiency of your hand’s nerve signal transmission has decreased by 18 percent,” she suddenly said. “Should we pause?”

"No need." He shook his hand. "As long as I don't die, that's fine."

Tighten the last screw, and the device starts. Water flows in slowly, passing through multiple layers of filtration before entering the cooling cycle.

“The system is running normally,” she said. “The extraction process can begin.”

He nodded, about to speak, when he suddenly caught a glimpse of something flashing in the corner of the monitor screen.

It's footage from a camera in the pool.

In the image, the blue light turned on again.

It wasn't a fleeting flash; it emitted a continuous glow, and the color was deeper than before, approaching indigo.

Moreover, the location has changed.

The green membrane that was originally floating on the eastern edge is now slowly gathering towards the center, as if it is being lifted up from below by something.

"Nana," he said, lowering his voice, "did you see that?"

“I see it,” she said. “A heat source mass has appeared 30 centimeters underwater. The temperature is 3.2 degrees higher than the surrounding area, and it is moving towards the sampling point.”

"Is it looking for traces we left behind?"

"The speculation is correct."

He stared at the screen, then suddenly bent down and pulled out a piece of insulating tape from under the table, wrapping it around his right hand.

"What are you doing?" she asked.

"Prevention is better than cure," he grinned. "Next time I go, I can't go empty-handed. Since it's afraid of metal conducting electricity, I'll wrap myself up tightly and see if it can still shake me."

"Aren't you going to wait for the extraction results before taking any action?"

"Wait?" He chuckled. "Wait for it to move the whole pool into the control room to say hello?"

He turned and walked toward the door, his steps heavier than when he came.

He stopped when he reached the door.

“Oh, right,” he said, “if I find that communications have been cut off after I go down there, don’t send anyone to find me right away.”

"Why?"

"What if I deliberately cut off the signal?" He glanced back at the screen. "Maybe I've reached an agreement with them and are signing a peace treaty. If you barge in, it'll make us look like we're not playing the game."

Before closing the door, he added, "Remember to keep track of the time. If there's no movement after twenty minutes, just assume I've been recruited."

The door closed.

On the surveillance footage, the blue light slowly rotated, like an eye submerged in water.

A notification suddenly popped up on the terminal inside the room:

Trace amounts of biological deposits were detected on the outside of the cryogenic chamber sample container.

Nana's robotic arm paused for 0.1 seconds.

She then brought up the underground sonar scanning interface and adjusted the detection frequency to the lowest setting to avoid disturbing the target.

On the screen, a thin, elongated wave extends from the direction of the pool, passes through the rock strata, and points directly below the main control room.

Her voice module remained silent for three seconds before finally issuing only a routine reminder:

"I suggest you change your gloves tomorrow."