The door clicked. Time slowed. Revlin blinked through the sweat, his hand glued to the raised iron handle, muscles committed to following through on the damned action of opening the death-trap door. Mladin, quick as a caged-in tiger, thrust himself to the ground, Vlostad, the opposite side of Revlin, backpedalled into Similya. Nowhere else for them to go, she wrapped herself around him and tugged them both to the floor, bowling over Yelsi and Tyomas. These two collapsed back onto Arban, like tumbled dominos. The recruit landed with a yelp on his injured arm. His bandage was flooded with a fresh red wave of blood.

Momentum pulled Revlin into the room against his will. A second click rang out, triggering an explosion, a ripple over and above his head. He ducked, neck retreating back into his spine on instinct. He waited for the impact to hit. Closed his eyes. Nothing. He almost stumbled and fell down the flight of stairs. He opened his eyes. The bomb had gone off, all right, but he'd survived. His lungs fought his mask's filter for oxygen. He skirted shock. Revlin had dropped his flashlight. It finished rolling about, its beam teetering to a stop on the edge of the topmost step, its crackling light illuminating a prone Mladin's legs through the doorway.

Revlin picked up the torch, bending slowly, goosepimples pecking his skin. He turned gingerly, and with the torch he examined the failed trap. A line of wire led from the door handle down, around the frame and then back up to some sort of improvised explosive resting atop the mantle. A burnt-out detonator of some sort still smoked. Next to these remains was a tube. As he stared at it, uncomprehending, it plummeted down. The tube's brittle plastic construction shattered as it struck the hard concrete. A nasty assortment of nails, all cruel and sharp, spilled out.

It was, or had been, an IED set with a short delay, designed to catch anyone coming through unaware. Lucky for Revlin, age had likely sapped its lethality. He explained his conclusion while his comrades picked themselves back upright. "Thank the Mother it failed. They'd put some type of bomb above the door." He shook his head in disbelief. "I should have a brain full of shrapnel." They all wore their masks, but the X5 breather units were no substitutes for ballistic helmets.

Mladin was straddling the doorway, peeking in, grim-faced but curious. "We open doors at arm's length from now on. Revlin, take a moment. When you're ready, clear the path down. We'll wait here; give you space."

"Understood." Revlin did take a moment. Shaky nerves let skilled men down, as did blurry vision. He swiped off his mask to clean the eye lenses before returning it. When his nerves had settled, he resumed his orders. He scanned what lay ahead: a part-rotted staircase leading down to a cramped landing area, and, he shifted the light to illuminate the dark, there was their objective, their way in; a heavy-set, solid-looking vault-style door. Behind that door was the Metro. Behind that door were their countrymen, just waiting to be liberated.

He moved slowly, cautiously, down the steps, taking extreme care. It wasn't long before new traps reared their heads. Thankfully these were easier to deal with. The lower half of the staircase was littered with old-fashioned mechanical bear traps. Revlin had an extendable baton in his light backpack. It was perfect for what he had in mind: he extended the rod and used it to spring each trap in turn. Ten minutes later he was at the bottom of the stairs. It was cramped down here. There was barely enough room for four people to stand together.

"Wire trap." He was convinced this was the last obstacle, bar the door of course. A line of wire ran diagonally across the dank floor. That meant there would be a bomb nearby. And there it was. When he was sure he understood the mechanism, he rooted in his backpack for pliers. Crouching low, like some primal hunter, he snipped the trigger line. It split in two with a soft plink. "It's safe, but watch your step," he called up, his final survey complete.

The Red Army unit trudged down the stairs in file. There wasn't enough room for them all to crowd around the vault door, so they stayed put on the staircase. Mladin did continue to the Metro entrance, and Yelsi pushed past the others to be by the commander's side; she either wanted to be among the first to enter the Metro and liberate their beloved Moscow, or she'd had enough of Arby's complaints at the re-opening of his bleeding arm. Revlin looked up. Vlostad and Similya were on the lower steps, toying with a deactivated bear trap. At the far rear was an exasperated Tyomas, his experienced hands full with a whining Arban.

"I need new bandages," groaned little Arby.

"We don't have that many-" protested Tyomas.

"That's not my fault!" They couldn't see of course, but they all guessed he was crying under his mask. "You all knocked me. Again! Ow!"

"Hold still," harrumphed the medic.

"My chest too… Ugh."

Revlin stopped watching Tyomas play doctor and turned back to the door. He found Yelsi looking at him. It was too dark to make out her eyes, but she gave a curt nod. He smiled under his own mask. He then looked to the stiff-backed commander. If he didn't know Mladin was there under that X5, he might think a gargoyle was hovering in the blackness, waiting to pounce on unsuspecting travellers.

"The door?"

"It's hard to tell. There might be a trap like that one," Revlin gestured up, "This door's a heavy one though. I don't think there'd be a trap like the one in Michurinsk." He referred back to an abandoned camp they'd picked through on their long journey to Moscow. That door's trap had been beyond Revlin's skill to disarm. In the end, the unit had given up trying to find out what was on the other side, though it must have been valuable to warrant such protection, and had just continued on their way.

"We'll swing it open then throw a grenade." Mladin nodded at his own plan.

Revlin gave the expected agreement. "My thoughts too. We can-"

"Contact!"

Everyone looked up, fumbling with their rifles and bringing them to bear.

"Contact, Arban?" snapped Mladin.

"There's something-"

"He's hearing things," Tyomas quickly interjected. "There's nothing there."

"No, no," Arby groaned.

Vlostad nudged Similya. She nudged him back with her shoulder.

"I heard it before. It was in … in the toilets," Arby muttered, swaying unsteadily.

"Tyomas?" Mladin ignored the younger man.

"I think that fall just now's been a bit too much. Come on, comrade," tried the medic, using his best bedside manner. "Man up."

"It's coming! I can feel it!" Arban broke into a fit of spluttering. He gave another shriek then collapsed, unconscious. Everyone flinched.

"He's out," reported a shaken Tyomas. The medic holstered his torch to take Arby in both hands. The reduction of light made being near the door suddenly uncomfortable.

The commander had heard enough. "Vlostad, Similya. Secure that door. We're moving on." While the couple advanced up the stairs, treading as stealthily as they could in their black combat boots, dodging the sprung traps, Mladin addressed Revlin and Yelsi. "Yelsi, get up the stairs. Revlin, open the door. I'll stay this side of it and throw a grenade when it's ajar."

The soldiers moved to comply. Revlin wrapped his hands around the door's large valve handle and set about pulling counter-clockwise. It didn't seem to move. The metal grated against itself. He paused to sling his rifle more securely, then redoubled his efforts. The handle gave off a horrible, wailing sound. Seeing him struggle, Mladin slung his rifle too and joined in the pulling.

"Do … you … think … they … locked it … other … side?" Revlin grunted.

"Maybe," said Mladin. "But no door … will … keep us out."

Vlostad and Similya overtook Tyomas and Arban. He followed her lead as she reached the door. There was no noise the way they'd come. What had rattled Arby? She paused and sniffed. Was there a strange smell? It was hard to tell. Maybe it was residue from the bomb. Whatever it was, something felt wrong. She signalled her intentions to Vlostad, who gave a curt nod of acknowledgement, then moved into the corridor.

"Yelsi," said Mladin, stretching his back.

Yelsi understood. Before she had to be given the order, she too slung her rifle and joined the two men at the valve.

Revlin took a deep breath. "On … three."

They went on three, tugging at the reluctant steel, and against their combined might it seemed to budge ever so slightly.

"More," wheezed Revlin. They pulled and pulled, as hard as they could. There was a snapping sound followed by a muffled clink, and then a sudden reduction in pressure. They all felt it. The handle started to turn more smoothly.

"I think we just … broke … a lock on the … other side."

"I'll take it from here," Mladin intoned. The other two relaxed and let the commander continue working the door. It was still far from an easy job, but he could manage. Revlin and Yelsi joined Tyomas in consoling Arby. The recruit had come around but had started babbling about monsters or some such nonsense.

Similya padded down the corridor, retracing their steps. Everything had seemed fine here not so long ago. Just another corridor in an abandoned building. No signs of animal life. But now she had that niggling feeling that there was something here. An alien presence. Had Arban jangled her nerves?

"Something wrong?" Vlostad asked.

Behind them was a dead end, as well as the side door leading to the staircase. Ahead of them was the turn they'd taken earlier, and then another door, several paces away, with a faded sign hanging above it. She could just about read it in what ambient light shone through cracks in the ceiling and holes in the walls. 'Toilets'. Neither her nor her partner had their torches switched on. She didn't want to give themselves away to whatever beast might be on the prowl, real or not.

"Arby said something about the toilets."

Vlostad frowned to himself. "How could he have heard something all the way in the toilets, from the staircase?"

It was Similya's turn to frown. "No. He said he heard it before."

Vlostad gave her an affirming nudge. Okay. I'm with you.

She advanced to the toilets, the archetype of vigilance. She checked the blind corner when she got to it. No sign that anything had passed by. All exactly the same as it had been when they'd first walked through. But there was still that strange smell. She couldn't place it. Was it the smell of mint? Or … wait. Was it just that her nose was tingling? She shook herself. "Way we came looks clear. Let's check the bathrooms."

Vlostad gave her a little salute. She went up to the door to the toilets. It hadn't been shut properly. It was ever so slightly open, resting shut on the lock. Not a good sign. She put her head against the wood, mindful not to bump her gas mask. There was something in there alright. She could hear laboured, pained breathing. Either something not human, or some animal in its death throws.

"Contact," she whispered. He nodded. She backed away. She flicked her flashlight on and pointed it at the doorway. Vlostad cocked his rifle. At his signal, she kicked the door open and stepped aside, shining in her torch. The door didn't so much swing open as fall flat down, crumpling in on itself. Vlostad fired away, loosing off silenced shots. As he fired, her eyes registered what she was seeing. The point of her flashlight moved up from the ragged corpse of a freshly killed beast, evidenced by the crimson blood still flowing from its torn body, and over the hulking black mass of a humanoid monstrosity. It could have been that she was too close to a firing weapon, silenced as Vlostad's rounds were, but a splitting headache came over her and a feeling of wrongness pervaded her thoughts. The smell, or sensation, or whatever the hell it was doubled in potency. Similya buckled and ran, Vlostad right behind her.

With a final clang, the door to the Metro announced itself open, ready, if not entirely happy, to permit the military unit access to the dark, dark tunnels of the Metro. This was it. As the two men had planned, Revlin positioned himself flat against the wall. Yelsi retreated up the stairs, shepherding Tyomas and Arban with her. Mladin flanked the door opposite Revlin. The heavy steel frame would open outwards. Revlin would push it so, and then Mladin would throw a grenade into the tunnel, in theory springing any further traps that might await them.

With deep a breath, prepared for the worst, Revlin leant out, put his left hand on the door and gave it a backwards shove. For a glorious second the door screeched open. Then it stopped. Friction. Drag. The door was half open, half shut. "See anything?" he whispered,

"Nothing." Mladin was blunt.

"If it was the same type of bomb as the other, that movement would have triggered it already."

The leader nodded. "Still, I'll throw the grenade."

"Wait," noted Yelsi, seeing what he planned to do. "There could be people there."

Mladin inched his face to the opening and yelled out, "Red Army. Stand back from the door." With that done, he produced a grenade, flicked the pin, and rolled it through the crack in the door.

All ears: Mladin's, Revlin's, Yelsi's, Tyomas' and Arban's pricked up at the sound of that grenade being cocked. All eyes: Mladin's, Revlin's, Yelsi's, Tyomas' and Arban's watched Mladin roll it out. Then everyone jumped, spooked, as Similya and Vlostad thundered back into the room, smashing down the stairs.

"Monsters!"

The grenade blew and the door shook a little. The soldiers swept up their weapons, unsure whether to rush in and follow the blast, or stay put and face the monsters. Revlin tried both. Aiming up the stairs over the heads of his friends with his rifle – Vlostad and Similya had forced their way down, in their urgency shunting their comrades towards Mladin and himself – and he tried to barge the door open with his back. There was still too much resistance.

Pawing Revlin out of the way, Mladin faced the door head-on and delivered a powerful kick. It swung open. "Out," he commanded, shoving the technician out into the tunnels. "Out," he repeated, grabbing Yelsi and bundling her out after him. Mladin knelt by the doorway, his weapon trained on the doorway. "Into the tunnel," he told the rest.

Tyomas and Arban scuttled through, followed by Vlostad and a shaken Similya. As the final members of his squadron made it out, Mladin saw something shift high above at the top of the stairs. He fired off a burst of shots. The figure didn't seem perturbed. He couldn't make it out. There wasn't enough light. He fired again, two more crisp bangs. The shape was edging down the steps. He'd seen enough. He rolled out into the tunnel. Sprawling on the ground, still aiming into the room to cover his men, he barked out, "Close the door."

"The monster," sighed Arban, leaning against the tunnel wall far back from the action. He seemed to forget where he was and what he should be doing.

Yelsi and Revlin rushed to push shut the heavy vault door. They then set about desperately turning that handle, locking out the monster.

"What was it?" asked Tyomas, in awe. Arban hadn't been hearing things.

"I don't know," replied Similya, honestly. Vlostad didn't speak.

"There," let out Yelsi. "Door's shut." She and Revlin backed away from it.

"More light." Mladin was up, inspecting the tunnel. "Keep your rifles ready."

His soldiers complied, flicking on their torches. Even with them, the Metro was too vast. They could see nothing in either direction.

"I'll set up the floodlight," suggested Revlin. He dropped his backpack to find it.

"We'll-" Mladin was cut off by the sound of the door. Its circular handle was being turned. From the other side. The animal that had spooked Similya must be an intelligent one. "Vlostad, Similya, hold that door shut! Revlin, get us that light. Tyomas, watch east. Yelsi, watch west. Arban…" He didn't bother giving the last man a command.

Similya and Vlostad raced to the door. They grasped the mechanism and desperately fought to keep it closed. The harder they struggled, the harder the thing did too. They started to lose ground to it. "Blyad!" she swore. "It's turning!"

Mladin was looking about the tunnel. He knew that to reach the heart of the Metro they'd need to head east, or right, if you were to face the door, but still he felt it prudent to investigate for any clues as to which way civilization might lie down here. He couldn't ignore Similya's cries. He joined her and Vlostad and gripped the handle firmly. He'd worn out his back battling to gain passage, now he wore it out further battling to deny passage. His heavy pack didn't help either. The monster was tough, fighting not just the natural friction of the battered steel but also the strength of three relatively healthy soldiers.

As they struggled against the monster, there was an instant explosion of light. They all blinked, taking a second to adjust. Revlin had gotten the light going, and now he too leapt to the door, though there wasn't enough handle for an extra pair of hands to take.

"Swap with me," said Vlostad. Revlin hastily obliged, giving his comrade respite.

Soon though Similya asked the same, and Vlostad took over from her.

The couple were both frightened, and that frightened Revlin. And despite four pairs of hands having grasped the handle, it felt unnaturally cold to his touch. What in the hell was this thing? They turned and turned.

"Hold it!" commanded Mladin. There was a real strain in his voice.

Just when they thought they could hold it no longer, there was an awful wrenching sound and the valve came free in their hands. They let it tumble free to a clunk. The door itself had lost the battle; the mechanism had broken. There was no way for the monster to come through now, except by brute force against thick metal.

"Is that it?" Similya asked.

Vlostad put his head to the door. "I think so." He couldn't hear it.

Silence reigned. With this onset of quiet, and with the warm orange glow from Revlin's floodlight revealing the mysteries of this eerie place, the soldiers found themselves taking in the details of the place they'd stepped into. The tunnel was about ten-men wide, if they stood shoulder to shoulder. The ambiguity of the dark leant it a near infinite-feeling, though they knew these tunnels had to end somewhere. The individual bricks of the thousand thousand that made up the tunnel could be picked out one by one, faint cracks visible between them. They arched up and around, surrounding them. Drips of phlegmatic liquid fell from the ceiling here and there. Whenever a droplet met a murky puddle, it gave a reverberated splash sound. The rest of the ground was a mass of debris, dirt, fallen brick, strewn rubbish, grizzled remains and worse, but cutting through all of this was a single train track, a crudely-maintained thing, bony, sinewy, reminiscent of a starving skeleton.

They all hovered, spread out, lost in their reflections. Tyomas finally broke the quiet. His humour had been sapped by their encounter with a monster. A monster that could open doors. He tried to search within himself for a joke to level the mood, conjure back their tight-knit spirit, but he couldn't find the words. Instead he noted, gloomily, "We're not getting back out that way."

Mladin's neck made a snapping sound as he shot Tyomas a look. Tyomas was glad they both had masks, so he was spared actual eye contact. He knew he was being rebuked. Before either man could pass further comment, Yelsi spoke up.

"There are people coming."

"People?" wondered Arby, clutching at his arm. None could see, but he was deathly pale beneath his X5. The encounter had left him touched.

"About two hundred metres. Maybe quite a large group," Yelsi added. "With our light, they'll have a good view of us, even from that distance."

"Everyone, weapons west. Tyomas, Arby, cover the rear. Revlin, kill the light. Flashlights on, but fingers on triggers."

It felt much colder when the orange glow died down from the floodlight.

The oncoming group drew near. They could be heard better than they could be seen: sniffing, stumbling, marching, stepping; it all echoed along the tunnel. It was hard to tell how many people there were, but they were certainly marching in the shape of a column. Did that make them military? Mladin assumed so.

Soon the arrivals were close enough to talk to. These people were in a column for sure, though a rag-tag column at that. Two thick-set men, in bedraggled military unit – Mladin was right – were leading the way. Behind them spilled a gaggle of others. Were they wearing some type of hat? Or were those sacks over their heads? Mladin hoped the former. Beyond the hooded figures, in a neater formation, were a couple of rows of other men, who Mladin assumed wore the same military uniform as those at the fore. Distributed amongst the crowd were weak flashlights, pump-action sorts: useful when there's no power, but no match for the equipment Mladin's soldiers had.

"Hold there," Mladin called out. "We are friendly. Identify yourselves."

The column halted. A single man's footsteps could be heard, clip-clapping as they raced from the back to the front of the crowd. This man weaselled into view, sliming past the two meaty guards at the head of the column. "Oberleutnant Gerbur." He looked at them with glossy eyes and wet lips. His black uniform was impeccably neat, possibly starched. He eyed them with a suspicious hunger, intrigued by the outsiders' appearances, their outlandish masks in particular. "Who are you?"

None of these people had gas masks. The men in uniform did have ballistic, battered but ballistic, helmets. Gerbur wore nothing but an oily lock of Aryan hair. Mladin wondered if the air here was safe to breathe, or if the people simply wore no masks because they'd run out over the years.

"Oberleutnant," mouthed Yelsi, quietly. A German title?

"We've come from outside the Metro. We are not strangers – we are the Red Army, your brothers. We are here to liberate you." Revlin felt pride surge in his chest as he said these words, just as he'd practiced.

TO BE CONTINUED