The alarm's red light was still flashing, but the sound had stopped.

Chen Hao stared at the heat map that Nana had brought up; the red area looked like a hot sheet of iron stuck to the ground in the North District. He reached out and touched the edge of the screen; it was cool.

"Not on fire?" he asked.

“No,” Nana said. “It’s the upwelling of underground heat, which may be related to the tsunami tremors.”

Will it explode?

"Won't."

Will it collapse?

"Possibly."

Chen Hao sighed, turned around and patted the walkie-talkie: "Susan, stop at the south wall for now, and bring everyone back."

Susan's voice came through the loudspeaker: "Again, are we changing the plan?"

"It's not about changing, it's about saving our lives," Chen Hao said. "If the pot is boiling underground, do you expect to put tiles on top of it?"

"Understood." She paused. "Then I'll take my men back to the living quarters and await further orders."

"While you're at it, check the inventory list." Chen Hao looked at Nana. "How many steel frames do we have left?"

Nana pulled up the data: "37% of the structural support components remain, and the inventory of connecting bolts is less than half of the original demand."

"Not enough to finish repairing the south wall?"

"not enough."

Chen Hao scratched his head: "Then we'll have to go out and look for it."

Carl was squatting at the door of the repair shop, eating compressed biscuits, when he heard this and almost choked.

"Going out again?" He looked up. "Last time you went out you almost got swept away by the waves, what are you looking for this time?"

"Steel," Chen Hao said. "Otherwise, if the wall leans and no one supports it, we'll be blown away by the wind sooner or later."

"Are you sure there's anywhere you can find some?" Carl asked, chewing on a biscuit. "This place is full of rotten rocks and dilapidated houses."

“An outpost,” Nana interjected. “There’s an abandoned supply depot 3.2 kilometers to the northwest. The blueprints show that its warehouse should contain precast steel beams and high-strength fasteners.”

“That sounds plausible,” Carl muttered. “What if we open the door and find only mice inside?”

"Then let's catch rats and eat them," Chen Hao stood up. "It's better than drinking seawater anyway."

Ten minutes later, the two shouldered their backpacks and set off.

Nana stayed at the base to monitor changes in heat flow, while Susan was responsible for organizing the remaining personnel to redistribute tasks. Before leaving, Nana slipped an electronic map into Chen Hao's bracelet.

“Follow this route,” she said. “Avoid the low-lying areas, the geology there is unstable.”

"Got it." Chen Hao shook his bracelet. "If you secretly turn off my location tracking, I'll take apart your speaker and play music from it."

“I’m not interested in following you,” Nana said. “But I suggest you don’t wander off; the power-saving mode only lasts for six hours of communication.”

"Alright, robot mom," Chen Hao waved his hand. "We're not kids anymore."

Carl walked ahead carrying his cutting tools, his footsteps crunching on the gravel. The sky was overcast, the wind was light, but it still picked up grains of sand from his face.

After walking for about forty minutes, they arrived at the outpost's perimeter.

The iron gate lay askew on the ground, as if it had been smashed open by a car. There were scratches on the wall and several fresh tire tracks on the ground.

“Someone has been here,” Karl said in a low voice.

“More than once.” Chen Hao squatted down to examine the traces. “At least two vehicles, coming and going frequently.”

"Stealing materials?"

"How about a picnic?"

The two went around to the side and climbed over the broken wall. The main warehouse door was ajar, and it was dark inside.

Chen Hao took out his detector and scanned the area: "No signal interference, temperature is normal."

"Shall we go in?"

"Go in."

As soon as I took a step, I heard the sound of metal clanging inside.

Someone is moving things inside.

Chen Hao raised his hand to signal them to stop and peered inside, pressing himself against the wall. Four people in protective suits were carrying steel beams out; the truck was already nearly half full.

"Hurry up!" one of them shouted. "This area is about to be cleared out by the other teams!"

"First come, first served!" another laughed. "Whoever's late deserves to starve!"

Chen Hao pulled his head back, leaned against the wall, and whispered, "Looks like we're not the only smart ones."

"So what do we do now?" Carl asked. "Fight and steal it?"

"Fighting is too much trouble," Chen Hao said, squinting. "Let's steal."

How to steal it?

"Go around to the back of the car and see if you can cut the power. I'll stall for time here."

Carl nodded, crouching low as he went around to the other side. Chen Hao took a deep breath, flung open the warehouse door, and shouted, "Hey! Which unit are you from?"

The four people inside were stunned.

"Who let you in?" The leader turned around, holding a wrench in his hand.

“I’m from C7 base,” Chen Hao pointed to the number on his uniform. “You’ve been using public resources without registering, do you know that you’re violating resource allocation regulations?”

"Regulations?" the man sneered. "Who cares about regulations these days? Come and snatch them if you dare!"

“I’ve already reported it,” Chen Hao said seriously. “A patrol team will be here to handle it within ten minutes.”

The two looked at each other, clearly wavering.

While they were talking, Carl quietly crept to the car, opened the hood, and unplugged two wires.

Chen Hao continued, "If you leave now, I can pretend nothing happened."

"Stop talking nonsense!" the man roared. "Get out of here! Or I'll beat you up!"

Chen Hao took a step back, then suddenly pulled a smoke bomb from his bag and threw it on the ground.

White smoke instantly spread out.

He turned and ran, shouting towards the corner, "Karl! Get two steel beams and use them to make way for the passage!"

Through the smoke, Carl had already pushed two steel beams into the abandoned side ventilation shaft. The two of them worked together to shove them in, then quickly evacuated.

When the smoke had mostly cleared, the group rushed out, but the car wouldn't start, and the steel beams were gone.

"Damn it! Someone's playing tricks!"

"Chase them! They can't have gone far!"

But they didn't give chase. The sound of another car engine came from afar, as if another convoy was approaching.

Taking advantage of the chaos, Chen Hao and Karl carried a steel beam and walked back along the back path.

"Finally got a little bit," Carl panted. "Although it's only one and a half."

"It's enough," Chen Hao said. "Let's go back and have Nana see if it can be modified."

Halfway there, the ground started to soften.

“This road doesn’t look right.” Carl stopped. “Have we traveled this way before?”

"I didn't notice." Chen Hao looked down. "It's probably from being soaked in rainwater."

He took a step forward, and the ground made a slight clicking sound.

"Don't move!" Carl shouted.

But it was too late.

Suddenly, the ground beneath their feet collapsed, and the two of them, along with the materials, fell down.

He landed on a pile of old wooden planks, kicking up dust. Chen Hao coughed a few times, touched his arms and legs, and found he could still move them.

"How are you?" he asked Carl.

“It’s nothing,” Carl said, sitting up. “It’s just that my butt hurts.”

Looking up, the pit entrance was covered by a large iron plate, and the surrounding gravel blocked the exit.

"A trap." Chen Hao looked up. "An old-fashioned, weight-bearing, trigger-type trap; it only collapses when you step on it."

Who set this up?

"I don't know." Chen Hao turned on his flashlight and shone it around. "But it's definitely not for catching rabbits."

The pit wasn't deep, about four meters, but the walls were made of rusty metal strips that stretched downwards like barbs, making it impossible to climb out.

“Contact Nana.” Karl took out his communicator.

The signal is weak and intermittent.

“Hey... Nana... can you hear me? We're... trapped... located... east of the outpost…”

Chen Hao was also trying his own equipment, and managed to get a connection.

"Nana!" he called out, "We're stuck in a pit, we can't get out! Can you see us from over there?"

After a brief silence, Nana's voice came through: "Received. Thermal imaging shows your vital signs are normal. Retrieving historical deployment data for this area."

"Hurry up!" Chen Hao said, "This place doesn't look very safe."

He swept the area with his flashlight again and suddenly noticed a black box in the corner, half-buried in the soil.

He crawled over and dug through the soil; it was an old-model circuit module, but the interface was still usable.

“Interesting,” he said.

Carl leaned closer: "What can you fix?"

"I don't know." Chen Hao weighed it in his hand. "But since someone specifically hid it here, it must be for a purpose."

Nana's voice rang out again: "This trap has been detected as part of the old-era resource protection zone defense system. The automatic rockfall mechanism is triggered by pressure sensing. To deactivate it, you need to disconnect the main control line or enter the authentication code."

"Which one is the main control line?" Chen Hao asked.

"Unable to be remotely identified. We suggest you locate the control box or the junction point of the lines."

“Easy for you to say,” Carl muttered. “We don’t even know where the door is.”

Chen Hao tied a flashlight to the steel beam and propped it up to illuminate the surroundings.

“Then let’s find one,” he said. “We can’t just sit here and starve to death.”

He moved to the side of the pit and felt along the metal strip. Some screws were loose, but the overall structure was still sturdy.

Suddenly, his finger touched a groove containing a thin thread that led to the black box.

“Wait a minute,” he said. “Is this thing connected here?”

He tried to insert the circuit module into the groove.

Click.

The metal plate overhead vibrated slightly, and a sliver of light shone through the gaps.