Rescue the "Doctor"

Anna's scream pierced the silence of the night like a knife.

Dragging sounds, struggling, the dull thuds of bodies hitting walls—those sounds came through the crack in the equipment room door, every detail terrifyingly clear. Lin Xiao could picture it: two Purge Squad members hauling Anna by the arms, her feet dragging across the floor, the hem of her lab coat sweeping through the dust, still fighting with every last bit of strength.

Su Ying's fingers rested on Lin Xiao's arm. No words were needed, but the pressure came through her tactical glove—she was asking with her eyes: Were they going to save her?

Lin Xiao's mind calculated furiously. Rescue success rate: if there were only two of them, he and Su Ying could ambush them and finish it quickly, possibly within three minutes. But the risks: gunfire would draw other Purge Squad members; their position would be completely exposed; their only escape route was through the drainage pipes, and it was unknown whether they were passable; Grey Falcon was still fighting desperately and unable to provide support.

Anna's value: a top biotechnology expert, someone the future Continental Hotel desperately needed. She knew the contents of the Radical Faction's experiments and might know the truth about Asset K. She still had a conscience, enough to be furious over the destruction of the samples.

Time was slipping away. The dragging sounds were moving downstairs, the footsteps growing more distant.

Three seconds. Lin Xiao made his decision.

He looked at Su Ying and nodded.

Hand signals flashed rapidly through the darkness.

Lin Xiao held up three fingers, then pointed downstairs—rendezvous below in three minutes. Su Ying nodded, pointed at herself, then toward the other side of the equipment room—she would go down first and clear the route. Lin Xiao gave a thumbs-up and drew his suppressed Glock 17 from his waist, checking the magazine.

Su Ying had already moved to the other side of the equipment room. There was a small window there, its glass shattered long ago, leaving only a rusted iron frame. She leaned out to observe. Moonlight fell across her face, outlining her cold, sharp features. Below lay an alley behind the building, packed with discarded construction materials and oil drums, thick with shadows.

She looked back at Lin Xiao, then slipped out the window, light as a cat. Lin Xiao heard a faint landing sound, followed by two muffled thumps—someone had been taken down.

He took a deep breath, gave the rooftop one last check through the door crack to make sure it was empty, then pushed open the iron door with its severed hinges. It gave a faint scraping sound, almost inaudible in the night wind. He slipped out sideways, moved quickly to the rooftop's edge, and looked down.

Su Ying had already dealt with two patrolling Purge Squad members. Their bodies lay in the shadows, their necks twisted at unnatural angles. She stood in the middle of the alley, looked up at Lin Xiao, and gave him the signal for safe.

Lin Xiao grabbed the rooftop drainpipe, suspended himself, then let go. He dropped three meters, rolled the instant his feet hit the ground, and bled off the impact. The concrete was cold and hard. Dust rose and stung his nostrils.

"Second-floor corridor in the building next door," Su Ying said in a low voice, pointing toward the building on the left. "They're taking her toward the stairwell. They should come out the back door."

Lin Xiao nodded, and the two moved along the wall. The alley reeked of rotting garbage, mixed with the smell of gunpowder drifting from afar. The ground was slick, whether from standing water or something else. As they passed the two corpses, Lin Xiao glanced at them—the Purge Squad members were both young, no older than twenty-five, their faces still frozen in the terror of death.

"They were brainwashed too," Su Ying said softly. There was no sympathy in her voice, only the calm acknowledgment of a fact.

"I know," Lin Xiao said. "But we have to survive."

They reached the end of the alley. Around the corner was the back door of the adjacent building. It was an old three-story warehouse, its outer walls mottled and its windows mostly broken. The rear door stood open, its frame still bearing signs of having been violently forced open.

Lin Xiao pressed himself against the corner and peered out.

The warehouse interior was dim, with only the faint green glow of emergency lights barely illuminating the corridor. Footsteps came from the direction of the stairs, heavy and hurried. Two dark figures appeared at the far end of the corridor, with a woman in a white lab coat between them.

Anna Koch.

She looked younger than Lin Xiao remembered, in her early thirties. Her short blond hair was disheveled and plastered to her forehead. Her glasses sat crookedly, and her left cheek was swollen red—she had clearly been slapped. Her lab coat had been torn open, revealing a gray experimental uniform beneath. Two Purge Squad members held her from either side, their movements rough.

"Let go of me! You lunatics!" Anna still struggled, her voice hoarse. "Those samples need to be kept at low temperature! You'll ruin—"

"Shut up." The Purge Squad member on the left smashed the butt of his rifle into her back.

Anna grunted, pitching forward and nearly falling. The other man grabbed her by the hair and forcibly dragged her onward.

They were heading straight for the back door.

Lin Xiao quickly retreated and signaled Su Ying: two people, escorting the target, exiting in ten seconds. Su Ying nodded, shrinking into the shadow at the wall's corner as though she had merged with the darkness.

Lin Xiao moved to the other side, where several discarded oil drums had been piled up. He crouched down, extended the barrel of his gun through a gap between them, and aimed at the doorway.

The footsteps drew closer.

"Where's the vehicle?" one Purge Squad member asked.

"In the rear alley. An armored vehicle," the other replied. "Hurry up. The captain said all technical personnel are to be concentrated in Area B."

"This woman is a real pain."

"She'll behave once she gets to Area B. I heard Blood Axe is personally handling the interrogations."

Lin Xiao placed his finger on the trigger.

The door opened.

The two Purge Squad members came out first, warily scanning the alley. Anna was dragged behind them, her eyes searching the darkness—perhaps for a chance to escape, perhaps for some hope of survival.

Now.

Lin Xiao pulled the trigger.

The suppressed pistol made a soft puff. The bullet flew from the muzzle, crossed ten meters, and drilled precisely into the left Purge Squad member's temple. His body jerked, his eyes went blank in an instant, and then he crumpled limply to the ground.

Almost at the same moment, Su Ying lunged from the shadows.

She moved so fast she was nearly impossible to follow. Her right hand seized the other Purge Squad member's gun hand and twisted hard—the crisp crack of shattering bone sounded especially clear in the silence. Her left hand was already around his throat, thumb pressing down on his carotid artery, index and middle fingers locking onto his cervical vertebrae.

The man did not even have time to make a sound.

Su Ying spun, using her momentum to hurl him into the wall. There was a dull thud as the back of his head struck the brickwork, followed by the sharp crack of his neck breaking. His body slid to the ground, eyes wide open in death.

The entire process took less than three seconds.

Anna stood frozen in place, dumbfounded. Her mouth hung open, but no sound came out. Moonlight fell across her face, revealing her pallor and terrified eyes.

Lin Xiao stepped out from behind the oil drums and hurried forward. He checked the two bodies first to confirm they were dead, then swiftly searched them—taking their communicators, magazines, and ID cards. Su Ying had already dragged the bodies into the shadows and covered them with discarded canvas.

"Dr. Anna Koch." Lin Xiao turned toward her, his voice low but clear. "Come with us. Now."

Anna finally came back to herself. She took a step back, pressing her back against the wall. "You... who are you?"

"The people who can save you," Lin Xiao said. "The Purge Squad was taking you to Area B. You know what that means. Interrogation, forced experimentation, or a direct execution."

"I... how do I know you aren't another Purge Squad faction?"

"If we were, you'd already be dead."

Anna's breathing was rapid, her chest heaving. She looked at Lin Xiao, then at Su Ying, her gaze shifting between them. Explosions sounded in the distance, firelight illuminating half the sky. Sporadic gunfire rang out like festival firecrackers.

"The samples..." she suddenly said. "The samples in the laboratory—if the temperature fails, they'll release neurotoxins. The entire base..."

"Where are the samples?" Lin Xiao asked.

"B-3 Building, second basement level. But the access control system has already locked down. Only my access card can open it." Anna pulled a blue keycard from her lab coat pocket. "If the Purge Squad forces the door open, or if a power system failure causes the temperature control to fail..."

Lin Xiao took the keycard. The plastic card still held her body heat, its edges worn from use.

"We'll deal with it," he said. "But now, you have to come with us. Otherwise, you'll be silenced or forced to continue those experiments—you know what experiments I mean."

Anna's face turned even whiter. She bit her lower lip, which trembled. A few seconds later, she nodded, stiffly but firmly.

"Okay," she said. "I'll go with you."

Lin Xiao slipped the keycard into the inner pocket of his tactical vest, then signaled Su Ying: prepare to withdraw. Su Ying had already checked both ends of the alley and confirmed they were safe for the moment. She returned to Lin Xiao's side, her eyes falling on Anna as she assessed the woman's physical condition.

"Can you run?" Su Ying asked.

"Yes." Anna took a deep breath and tore off her ruined lab coat, revealing her experimental uniform and sneakers beneath. "I run ten kilometers every week."

"I hope you're not lying," Su Ying said. Then she turned to Lin Xiao. "Back the way we came? Through the drainage pipes?"

Lin Xiao shook his head. He took out the base map—the wrinkled paper map unfolded beneath the moonlight, several locations marked in red pen.

"The drainage pipes are too slow, and they may be blocked." His finger moved across the map. "East from here, through the warehouse district, there's a maintenance passage leading to the base perimeter. Wolf and Nightingale are at Backup Rendezvous Point B, 1.2 kilometers from here."

"The Purge Squad has definitely sealed off the main routes," Su Ying said.

"That's why we'll go underground." Lin Xiao's finger stopped on a marked point on the map. "Here. The Old Ventilation Duct System. The entrance is in the warehouse basement, and the exit is at an abandoned observation station three hundred meters outside the base wall."

Anna leaned closer to inspect the map. She had straightened her glasses, and her eyes were focused. "The old ventilation system? It was abandoned ten years ago. The structure might be unstable."

"Still better than staying here and getting shot," Lin Xiao said, folding up the map. "Move."

They left the alley and moved along the building shadows. The warehouse district was deathly quiet. Most of the buildings were dark, with only a few windows glowing green from emergency lights. Shell casings, shattered glass, and dark red bloodstains littered the ground. The air was thick with gunpowder, blood, and the pungent scent of some leaking chemical agent.

Lin Xiao took point, Su Ying covered the rear, and Anna was protected in the middle. Their footsteps echoed through the empty streets, every landing careful. Lin Xiao's ears caught every sound around them: distant gunfire, explosions, and farther away, the roar of armored vehicle engines.

As they passed an intersection, Lin Xiao suddenly raised a hand—stop.

Everyone crouched down and hid in the shadow of the corner.

Lin Xiao leaned out to observe.

On the other side of the intersection, a squad of Purge Squad members was patrolling. Six people, fully armed, their tactical flashlights sweeping across the street and building walls. They moved slowly, checking every corner carefully.

"Detour," Lin Xiao whispered, pointing toward a narrow alley on the left.

They backed away and entered the alley. It was darker here, with high walls on both sides and crisscrossing antennas and clotheslines overhead. The ground was slippery, garbage floating in the puddles. Anna stepped on something soft and nearly cried out—it was a dead rat, its body already flattened.

Su Ying caught her, pressing a finger to her lips: quiet.

They continued forward. At the end of the alley stood an iron door, heavily rusted, its lock already broken. Lin Xiao pushed it open gently, and its hinges gave a piercing groan.

Beyond it was a small parking lot, containing several abandoned trucks and an armored vehicle.

An armored vehicle.

Lin Xiao's heart skipped a beat.

The vehicle sat in the middle of the lot. Its headlights were off, but its engine still rumbled quietly. A Hydra insignia was painted on its body. Its side door stood open, a faint red glow spilling out from within. Two Purge Squad members leaned against it smoking, their cigarette tips flickering in the dark.

Worse still, footsteps and shouts came from the other side of the parking lot—at least four or five more people were approaching.

"The disturbance just now came from this direction!"

"Check every building!"

"The captain said not a single one can be spared!"

Lin Xiao rapidly scanned the surroundings. The parking lot was enclosed by buildings on three sides, its only exit blocked by the armored vehicle. They were trapped.

Su Ying had already drawn her dagger, her eyes cold. Anna tightly covered her mouth, her body trembling.

Lin Xiao's mind raced. Force their way through? Impossible. There were too many enemies, and they had an armored vehicle. Hide? There was no suitable cover in the parking lot, only several abandoned trucks, but the Purge Squad would definitely search them.

There was little time. The footsteps were getting closer, and flashlight beams had already swept over the edge of the parking lot.

Then static crackled in Lin Xiao's earpiece, followed by Grey Falcon's hurried, weakened voice. It came in fragments, mixed with gunfire and explosions:

"Captain... we're surrounded... at the Maintenance Workshop... can't hold out much longer... Blood Axe is leading them personally... they... ah!"

A cry of pain, then the dead tone of a severed transmission.

Lin Xiao's expression changed.

Grey Falcon's situation was critical. Blood Axe—the Purge Squad's ace commander, infamous for brutality and efficiency. If Grey Falcon fell into his hands, he was as good as dead.

And right now, they themselves were trapped in Extremis.

Near the armored vehicle, the two smoking Purge Squad members seemed to hear something. They crushed out their cigarettes, raised their guns, and headed toward the corner where Lin Xiao and the others were hiding.

The flashlight beams swept across the wall, only three meters away.

Two meters.

One meter.

Lin Xiao tightened his grip on his gun, finger hooked around the trigger. Su Ying's body tensed like a leopard preparing to pounce. Anna closed her eyes and stopped breathing.

The beam swept over the wall above their heads, then turned toward—

It stopped.

The Purge Squad member's flashlight shone into the shadow at the corner, onto the tip of Lin Xiao's shoe.

"Someone's there!" someone shouted.

Gun barrels rose.

Lin Xiao was about to fire—

Bang!

A shot rang out.

But it did not come from the Purge Squad members.

A bullet flew from the other side of the parking lot and pierced the helmet of the Purge Squad member holding the flashlight. Blood burst out, and the body fell backward.

Before the second Purge Squad member could react, a second shot rang out, and he fell as well.

The red glow inside the armored vehicle abruptly went out. Its engine died.

The entire parking lot fell silent.

Lin Xiao froze. So did Su Ying. Anna opened her eyes, staring blankly at the scene before her.

Footsteps sounded from the other side of the parking lot, calm and unhurried. A figure emerged from the shadows, a suppressed sniper rifle in his hands.

Moonlight fell over him, revealing a familiar face.

Wolf.

"Captain." Wolf walked up to Lin Xiao, wearing a tired but resolute smile. "Nightingale cracked their communications channel and heard you were in trouble."

Lin Xiao let out a breath of relief, but immediately asked, "What about Grey Falcon?"

"Before communications were cut off, Nightingale pinpointed his position." Wolf's expression grew grim. "The Maintenance Workshop, eight hundred meters from here. At least twenty Purge Squad members, with Blood Axe commanding personally. Grey Falcon's team has... maybe three people left. They're all trapped inside."

"Is Backup Rendezvous Point B secure?"

"Secure. Nightingale has set up interference devices and temporarily blocked surveillance in that area." Wolf glanced at Anna. "And she is?"

"Dr. Anna Koch, biotechnology expert," Lin Xiao introduced briefly. "We need to get her somewhere safe."

Wolf nodded, then pointed at the armored vehicle. "The vehicle still works. The keys are on the bodies. We can drive out through them, but it'll make a lot of noise."

Lin Xiao considered it. Driving was indeed the fastest option, but they would become moving targets. On foot, they would be slower but more concealed.

He looked at Anna. Her face was pale, but her gaze was steady. She had been captured, rescued, and forced to flee, yet she could still stay calm. Her mental fortitude was solid.

"Doctor," Lin Xiao said, "do you know the exact location of the entrance to the old ventilation system?"

Anna nodded. "It's in the B-3 Building basement, but that place is now..."

"Controlled by the Purge Squad," Lin Xiao finished. "So we can't go there."

He took out the map and unfolded it again. His finger moved across it before stopping at a marked point. "Here. Wastewater Treatment Plant. The underground pipes connect to the old ventilation system. The entrance is inside an inspection manhole."

"The Wastewater Treatment Plant is four hundred meters from here," Su Ying said. "But we have to cross the open training ground. No cover."

"Then we need a distraction." Lin Xiao looked at Wolf. "Can you create some chaos?"

Wolf smiled. "Captain, have you forgotten what I do? Nightingale gave me a few little toys."

He took several cylindrical devices from his backpack—remote-detonated stun grenades and smoke grenades.

"Set them on a delay and create a disturbance on the far side of the training ground to draw the Purge Squad's attention," Wolf said. "You cross the training ground while they're distracted and enter the Wastewater Treatment Plant. I'll drive out through another route and draw off the pursuers."

"Too dangerous," Su Ying said.

"Safer than staying here and waiting to die." Wolf had already begun setting the detonation timers. "They'll go off in thirty seconds. Start moving toward the training ground now. Once you hear the explosions, sprint at full speed."

Lin Xiao looked at Wolf. This intelligence officer was usually quiet, but he never backed down when it mattered.

"Come back alive," Lin Xiao said.

"I will." Wolf grinned. "Captain, the Continental Hotel hasn't even been built yet. I can't die."

He turned and ran toward the armored vehicle, jumping into the driver's seat. The engine roared to life, and the headlights suddenly came on, their blinding white beams ripping through the darkness.

"Go!" Lin Xiao told Su Ying and Anna.

The three rushed out of the parking lot and sprinted toward the training ground. Their footsteps echoed across the empty streets. Lin Xiao could hear his own heartbeat, Anna's ragged breathing, and the gunfire growing nearer in the distance.

They reached the edge of the training ground. It was an open expanse once used for soldiers' physical training, now completely deserted. The ground was packed dirt, scattered with training equipment: tires, sandbags, and barbed-wire obstacles. Beyond it stood the base wall, searchlight beams sweeping across the night sky.

There was no cover. Four hundred meters of open ground—if the enemy spotted them, they would be live targets.

Lin Xiao crouched behind the cover at the training ground entrance and looked at his luminous watch.

Twenty-five seconds.

Twenty seconds.

He could hear the armored vehicle's engine roaring away. Wolf was deliberately making noise to draw the pursuers away.

Fifteen seconds.

On the other side of the training ground, the Purge Squad's flashlight beams were moving. There were at least ten of them, chasing in the armored vehicle's direction.

Ten seconds.

Anna's breathing grew more and more ragged. Su Ying placed a hand on Lin Xiao's shoulder and gave it a light squeeze—she was ready.

Five seconds.

Four.

Three.

Two.

One.

Boom!

Explosions erupted from the other side of the training ground. Not one, but three in rapid succession. The deafening blasts of stun grenades shook the ground, while smoke grenades spewed dense white smoke that rapidly spread and obscured the entire area.

Shouts from the Purge Squad, gunfire, and chaotic footsteps carried over.

"Now!" Lin Xiao barked.

The three of them burst from cover and sprinted at full speed.

Mud sprayed beneath their feet as training equipment flashed past them. Lin Xiao could hear his own ragged breathing, Su Ying's light but steady footsteps, and Anna's muffled groans as she gritted her teeth and pushed on. Four hundred meters was not far for trained personnel, but sprinting through a hail of bullets made every meter a test between life and death.

The smoke began spreading toward the center of the training ground, white fog surging toward them like a tide. Lin Xiao charged into it, and his vision blurred instantly. He could only rely on memory and his sense of direction, listening for Su Ying's and Anna's footsteps beside him.

Gunfire came from outside the smoke. Bullets whistled past, striking the dirt and kicking up dust.

"Duck!" Su Ying suddenly shouted.

Lin Xiao instinctively bent down. A bullet grazed over his head and hit a tire ahead, producing a dull thud.

They kept sprinting. His lungs burned, and the muscles in his legs began to ache. Anna was visibly slowing down. After all, she was not a professional fighter.

Su Ying grabbed Anna's arm and practically dragged her forward.

"Hang on!" Su Ying said. "We're almost there!"

Lin Xiao had already spotted the outline of a building at the end of the training ground—the Wastewater Treatment Plant. It was a low concrete structure with stained outer walls and shattered windows. The entrance was on the side: a half-underground maintenance shaft.

Fifty meters.

Thirty meters.

Ten meters.

They rushed to the outer wall of the Wastewater Treatment Plant, pressing their backs against the concrete as they gulped air. Smoke had already drifted this far, reducing visibility to less than five meters. Gunfire continued, but its direction had changed—the Purge Squad had been drawn away by Wolf and the explosions.

Lin Xiao found the maintenance shaft. Its cover was a rusty iron plate, with pry marks around the edges. He shoved it open, and the cover let out a piercing screech of metal scraping against metal.

The shaft opening was pitch-black. A damp, rotten stench surged up from below, mingled with the pungent odor of sewage and chemical agents. An iron ladder extended downward, vanishing into the darkness.

"Go down," Lin Xiao said. "Su Ying first, the doctor in the middle, and I'll bring up the rear."

Su Ying did not hesitate. She swung herself into the shaft. The iron ladder groaned with a creak, but it was still sturdy enough. Anna followed, awkward but resolute. Lin Xiao entered last, taking one final look at the training ground before climbing down—

The smoke was beginning to clear. The Purge Squad's flashlight beams were moving, but they were still some distance away.

He pulled the cover shut, leaving a narrow gap for observation.

Below them was total darkness, broken only by the faint beam of Su Ying's tactical flashlight. The space was larger than expected: a circular vertical shaft roughly two meters in diameter and ten meters deep. The walls were damp concrete, covered in moss and mold. At the bottom was a cement platform connected to a horizontal pipe one and a half meters wide, large enough for a person to crouch through.

The sound of flowing water came from inside the pipe, along with the low hum of some machinery.

"The connection to the old ventilation system is at the end of the pipe," Anna's voice echoed through the darkness. "After about fifty meters, turn left. There's a maintenance door."

"Lead the way," Lin Xiao said.

The three entered the pipe. It was even darker inside, and the air was more stagnant. The flashlight beam revealed the pipe's inner walls—corroded metal, peeling paint, and thick layers of dust. The floor was slick with shallow sewage, making wet slapping sounds beneath their feet.

They moved forward while bent over, not very quickly. Their footsteps and breathing echoed through the pipe, along with the faint sounds of distant explosions.

After about thirty meters, Anna suddenly stopped.

"What is it?" Lin Xiao asked.

Anna crouched down and shone her flashlight at the inner wall of the pipe. There was a faded red marking that was still recognizable: an arrow pointing left, with a line of small text beneath it—"Ventilation System B-7."

"This is it," Anna said. "Turn left. The maintenance door is farther in."

They turned left. The pipe narrowed here, leaving room only to squeeze through sideways. Lin Xiao forced his way through and aimed his flashlight ahead—a rust-covered iron door was embedded in the pipe wall, its handle rusted solid.

"We need tools," Su Ying said.

Lin Xiao pulled a pair of multipurpose pliers from his tactical vest, clamped them around the handle, and twisted hard. The corroded metal shrieked, but the handle did not budge.

"Let me try," Anna suddenly said.

She pulled a small bottle from the pocket of her lab coat—laboratory lubricant spray. She sprayed the lock and hinges several times, and the clear liquid seeped into the gaps in the rust.

"Now," she said.

Lin Xiao exerted himself again. This time, the handle turned. It was difficult, but it was moving. He gritted his teeth and threw his full strength into it.

Click.

The lock opened.

Lin Xiao pushed open the door. Stale air rushed out, carrying the smell of dust and mold. Beyond the door was another space—the main duct of the old ventilation system. It was more spacious than the pipe, allowing them to stand upright. The inner walls were metal grating, and the floor was covered in non-slip steel plates. Far ahead, ventilation fan blades sat motionless, covered in cobwebs.

The flashlight beam shone ahead, dust dancing within it.

"Clear." Su Ying entered first and checked the surroundings.

Lin Xiao and Anna followed. Once the door was shut, the sounds outside were almost completely cut off. This place was like an isolated underground world, with only their breathing and footsteps echoing through the metal ducts.

Anna leaned against the wall and finally let out a breath. Her body was trembling, whether from the cold or lingering fear.

"We're... safe?" she asked.

"For now," Lin Xiao said. "But Grey Falcon is still in danger."

He pressed his communications earpiece. "Nightingale, can you hear me?"

A brief burst of static sounded, then Nightingale's voice came through, clear but tense. "Captain! Where are you? Wolf just drew the pursuers away, but he's trapped in the warehouse district too!"

Lin Xiao's heart sank.

Wolf was in danger too. Grey Falcon was on the brink of death. And they, though temporarily safe, were still inside the base, with no known way out.

"Nightingale, report your position and security status." Lin Xiao forced himself to stay calm.

"I'm at Backup Rendezvous Point B, safe. But the surveillance shows the Purge Squad is closing in around this area. They'll arrive in twenty minutes at most." Nightingale's voice was urgent. "Captain, we need an evacuation plan."

Lin Xiao looked at Anna. "Doctor, where exactly is the exit from this ventilation system?"

Anna closed her eyes, trying to remember. "An abandoned observation station, three hundred meters outside the base perimeter. But the exit is in the station basement. The door may be locked, or blocked by debris."

"Is there a backup exit?"

"Yes... another branch of the ventilation system leads to a drainage ditch outside the base. But that route is more dangerous. It may have collapsed, and there may be chemical contamination."

Lin Xiao thought it over. Two options: the observation station exit might be blocked, but it was relatively safe; the drainage ditch exit might be open, but the environment was dangerous.

There was not much time left.

He had to make a decision.

And at that moment, a sound suddenly came from deep within the ventilation duct.

It was not their footsteps.

It was something else.

The sound of metal scraping.

And... breathing.