The walls of the cave closed in around them in a veritable dome of oily black, completely shutting them off from the outside world. With her night-sight goggles Amber could clearly see the terrified faces of the mining personnel trapped within, many of them sporting bruises, cuts and a handful of more serious injuries sustained in the collapse.

These were the lucky ones. Over twenty of their colleagues had been killed instantly when one of their Tecton mining lasers had misfired, erasing a series of vital support ribs with a single blast and bringing hundred of tons of rock crashing down on the miners. The mine entrance was smashed to rubble, leaving the survivors trapped in an airless, lightless pit, unreachable by normal means.

And that was when the station operators above had screamed out to Blink for help. The administrators of Jalur VIII ran a tight, threadbare operation out on the smoky, arid world, and lacked any means of extracting the trapped workers. On top of the loss of life, the dividend payouts to the miners' families would already be skyrocketing, so much so that it might cripple the whole operation. If they couldn't get the survivors out, the entire mining complex would have to be shut-down. A cold justification, perhaps, but one that had leant extra urgency to their desire to rescue those who were still alive.

Amber passed a breather to one of the miners, helping the woman as she fumbled in the darkness to fix it to her face, able to see through the night-sight goggles, a ragged smear of dried blood that ran down the miner's temple. The first thing the operatives had done upon arrival was Blink into the disaster area, loaded down with spare oxygen tanks and breather masks for the survivors. One commodity they needed to buy was time.

"Easy," Amber said softly. "Take slow breaths."

The woman nodded, clasping a hand gratefully over the mask to hold it, even though it vac-sealed in place. Steering her with a gentle hand, Amber sent her towards the flickering guide-beam of Hekket's torch. The sandy-haired medic stood with Uther, their veteran tech, and the survivors of the cave-in. After an examination of the interior coupled with blueprints provided by the station operators they'd identified a number of structurally safe zones that should withstand the forces they were about to unleash in their attempts to free the trapped miners.

Amber turned to check on the progress of her squad-mate who also stood handing out masks and acting as a guide. To her relief, the slim-framed girl standing opposite her in the passage seemed to be in her element.

With their squad leader suspended, Hammerhead Squad had been left short-handed, something Smith wouldn't tolerate. So, in Darien's absence he'd assigned them Bryn Harvard, a rookie operative fresh out of her training. Initially, Amber had braced herself for a tumultuous transition, the memory of the last unwanted transfer still raw in her mind. This time, however, the integration ended up being smoother than she could have hoped.

A lot of that was because of how Bryn had ended up with Blink – a refugee from the murderous experiments of six months ago that claimed dozens of lives that could have been better used in service of the Blink organisation. The now fourteen-year-old Bryn Harvard already showed formidable skills in eluding those criminals. That, coupled with the fact that half the squad had been present to see it, meant that she got a healthy reception from her new comrades.

And she was holding up here as well. The dark didn't bother the hard-featured teenager and she moved with a confidence well beyond her years as she directed confused, reluctant workers to their safe zones. Looking past her, Amber narrowed her eyes as she observed the dark figures at the far end of the cavern.

Their current squad leader, Niamh O'Toole, was busy double-checking the ring of charges that Idas had spent the last hour painstakingly positioning. The only workable plan they could put into action was to find a stable point on the interior of the collapse and trigger a focused incendiary blast that would fuse them a temporary tunnel out, something that had been impossible to gauge from the outside.

So far she'd directed this mission – as she had every other – with the calm, firm ease of a veteran, but there was a dark cloud hanging over her authority. When Darien Flint had earned himself a suspension after their last mission, Niamh dutifully stepped into the breach as his second in command.

But Amber hadn't forgotten, or forgiven, the act of cold-blooded murder that had caused the girl's abrupt promotion. With their quarry finally cornered and defenceless, Darien had shot Theodore Logan, ex-Blink operative, in the head and ended his life. When she joined Blink, Amber didn't sign up to be a killer, but all she'd been able to do was helplessly watch the horrific scene unfold. She wasn't likely to forget that, although she hadn't pulled the trigger, Niamh had backed Darien's actions every step of the way.

With a heavy sigh, she forced those thoughts from her mind, returning to the task at hand. Whatever misgivings she harboured, the most important thing right now was to get the last of the miners out of this tomb alive.

"Looks like that's everyone," Bryn told her as she sent the last survivor on their way. Crossing the space between them, the slender operative rested her hands on her lightweight lance carbine, glancing left and right, looking expectantly to Amber. "What do we do now?"

This would take some getting used to. Amber was barely nineteen, but by Blink operative standards she was already a veteran, having been on numerous missions, many of which had been incredibly dangerous, and she'd come out alive on the other side. Bryn treated her with an almost reverent deference that she found more than a little unsettling.

"Good work. Now I think it's time to blast our way out of here," she replied, before turning, cupping a hand around her mouth and calling to their squad leader. "Niamh, all the civvies are kitted with breathers and in their safe zones!"

"You better join them," the flame-haired girl shouted back. "Charges are primed!" A moment later Niamh loped across the cave, with Idas's hulking shadow following her. As the pair reached them, Amber and Bryn fell into step, and the four operatives jogged through the gloomy underground prison until they reached the huddled band of terrified miners. Some sported cuts and bruises, while others had suffered far more grievous injuries.

Hekket stood watch over the most extreme case, a man whose skull had been fractured by a falling rock. He lay on a stretcher, his head swathed in field bandages and blood, and she knew if they didn't get him out of the cave-in in the next couple of hours he would be as good as dead. She moved up alongside him; touched his arm.

"How're we looking?" she asked quietly.

He gave a fatalistic shrug. "I've done everything I can do. Now we need to get him out of this place."

"We'll get it done."

"Damn right we will," Niamh interjected, her voice hard with determination. "Once those charges go we won't have long. Idas, you and Uther grab the stretcher and get this guy out to the medics. Don't stop – don't wait for us – just go."

"We'll get him out," Idas assured her, and he and Uther took up their positions.

With her hands tightly wrapped around her carbine, Niamh moved in close to the others, speaking in a low voice. "This should be a precision blast, but once there's a hole in that wall the structural integrity of this place will go to hell. You need to get everyone moving as fast as you can. Amber, you hang back, make sure the stragglers are moving. But no heroics, okay? If the place starts coming down I want you to Blink out of here. You understand me?"

"Yeah, I get it." Amber gave her a stiff nod.

In theory all of them could have Blinked clear, as soon as charges were triggered, but what kind of message would that have sent to the people they were attempting to rescue? If this plan was too dangerous for her, then it was too dangerous full stop. She had no plans to leave anyone behind today.

"Alright, everyone!" Niamh shouted, instantly wrenching all attention toward her. "We have one minute until the escape charges detonate. Avert your eyes from the flashpoint and keep your breathers secure. When the path is cleared follow the directions of the operatives nearest to you. The exit will not be a large one, so you cannot all move at once. Those who are injured: front of the queue. Everyone else form up two-by-two." She dropped her voice again, addressing her operatives once more. "Bryn, Hekket, flank out and make sure they don't just stampede for the exit when we blow this open."

The pair dispersed into their positions without a word, and Amber took up her lonely vigil right at the back, furthest away from the charges. She kept focused on the task at hand, shoving the potential dangers to the back of her mind, something she'd learned to do quite easily over her tenure as a Blink operative. In comparison to some of the things she'd encountered, a collapsing mine seemed almost tame. More than one nervous glance came her way from the miners up ahead, but her calm demeanour seemed to rub off on them, and they squared their shoulders, ready to do what they had to do.

Through the night-sight goggles she saw Niamh raise her hand high for them to see, clutching the battery-sized detonator. She braced herself for the explosion that she knew was just seconds away. As though in slow motion the other girl's thumb curled down against the button.

There was a violent, fizzing flash and a tidal wave of light crashed over them as the charges detonated, vaporising a precisely calculated cylindrical void through the mountain of rock and rubble. Amber found she was holding her breath as she heard the whole cavern groan and a low, frantic murmur of surprise rippled through the miners.

"Nobody move!" she heard Idas growl above the crumbling of debris. They waited, precious seconds dragging by as the dust settled. She shoved the night-sight goggles up onto her forehead as light from their improvised exit gushed into the cavern in a fat, cream-coloured beam. When the dust had settled she could see a neat tunnel bored through the debris, a little over a meter and a half in diameter.

"Idas, Uther," Niamh's axe-sharp bark hacked through the air. "Go, now!"

Instantly the two operatives set off, the stretcher bearing the critically wounded miner slung between them. Without breaking stride out in front, Idas hitched a leg up and dug a heel into the lip of the tunnel, propelling himself inside in one fluid motion. With the other end of the stretcher Uther matched the movement with impressive smoothness, and together the pair vanished into the tunnel with their burden.

"Alright, everybody else, move two by two!" Niamh shouted. "Go!"

The terrified miners didn't need to be told twice. In a jumble of barely controlled chaos they stampeded toward the aperture, with Bryn and Hekket shepherding them along, snapping terse, contrite commands to keep them from causing a jam at the tunnel-mouth.

Bringing up the rear, Amber made sure they missed no-one, her sharp eyes flashing constantly left and right, searching for any stragglers. One of the back-markers tripped and she instantly dropped to a knee at the man's side, hooking an arm under his and hauling him upright with a single, sharp tug. He didn't even glance at her, eyes wide with desperation to escape the claustrophobic gloom of the collapsed mine.

The first pairs reached the tunnel, and under firm, calm direction from their two Blink chaperones, the miners began an orderly procession despite their obvious terror. For a couple of minutes everything seemed under control.

Then an ominous rumble passed through the cavern.

Amber looked up instinctively, and a twang of urgency shot through her when she saw cracks beginning to form in the rubble above their improvised escape shaft. The incendiary charges, precisely positioned, had cauterised the surrounding rock into a semi-sold passage, but the stability was already beginning to fade.

At the back of the group, however, all she could do was wait and will them on, watching with growing anxiety as the cracks spider-webbed through the structure. She sidestepped deftly as a rock the size of a football broke free from the ceiling, falling and smashing apart where she'd just been standing. The nearest miners started to panic.

"It's okay," Amber snapped sharply, completely ignoring the piece of fallen rubble and pointing at the passage. "Just keep moving."

Her brusque confidence seemed to galvanise them and soon the last pairs had reached the tunnel mouth. Once the civilians had been eased into the passage, Amber nodded to Bryn and Hekket who stood flanking the tunnel.

"Go, I'm right behind you," she told them, doing her best not to think about the pieces of masonry coming loose behind her. Side by side her companions clambered in and set off down the tunnel. Amber was about to follow them, but a cracking sound arrested her progress. Her eyes narrowed and she glanced straight up, only to see a huge hunk of rock falling toward her.

Her lightning reflexes saved her life as she bounded backwards, leaving a lump of sold sandstone four feet across the shatter against the cavern floor. She stumbled a couple of steps back, then bounded forward, jamming a foot down against one of the fragmented lumps of rock and propelling herself into the passage.

Cracks worked their way through the cylindrical tunnel, but even as she scrambled forward, Amber knew her chances of making it to the other side by normal means were slim. She saw Hekket skid out of the far end and whirl around, holding out a hand and frantically beckoning her forward, his eyes wide. Another rumbling crunch sent more fissures through the tunnel and she knew there was no chance of getting through it by normal means.

In another time that thought might have filled her with panic. Now, after seeing some of the worst things the galaxy had to offer, Amber didn't even hesitate. She stopped dead, planting her feet and closing her eyes, ignoring the ominous rumbling that echoed in her ears. The shouting voices faded away into nothingness and she focused her mind to Blink. The distance she needed was small, a comparative hop by her standards. Calculating her mass and a fifteen meter jump forward, she placed herself well outside the tunnel and away from falling rocks. In the final instant, she shunted the equation to land herself three meters above the ground as a precaution. That way the worst that could happen would be falling on top of another human being, instead of materialising inside of one.

Then she made the Blink happen. For the smallest fraction of a second the sensation of not quite existing at all enveloped her – a completely cold, quiet emptiness. Before her mind could fully grasp the sensation it disappeared, and she was surrounded by light, pure burning daylight.

Her eyes snapped open. Then she was falling.

A yelp of surprise slipped from her lips as she plummeted earthwards. Protected by her body armour there was no real prospect of injury from falling barely three meters, but she couldn't contain the instinctive response to the sensation. Just before she hit the ground she curled up, protecting her head with both hands, and then her body thudded to the arid, dusty earth of Jalur VIII.

A jolt of pain rattled through her bones, but the tungsten-fibre weave of her armour absorbed the brunt of the impact. With a groan, she unfolded her body and rolled into a sitting position, looking back to see the temporary escape tunnel finally give way. Blowing out her cheeks in a sigh of relief, she leaned back, propped up on her elbows. The miners were still looking inward, horrified expressions on their faces, but the five Blink operatives already knew she'd made it out. Their faces turned to her; eyes brightened along with a series of smiles.

"There she is," Hekket laughed, bounding over to her as the colonial medical teams descended on the injured miners. He dropped into a crouch by her side, extending a hand to help her up. "Cut that one close. You okay?"

"Never better." She took his hand and he pulled her to her feet as the others gathered around them. "All in a day's work, right?"

"At least for us."

"Nice work everybody. That's all the survivors accounted for," Niamh told them, a satisfied smile splitting her vulpine features. She unclipped her carbine from its strap, letting it hang loose in one hand. Sparing a glance back at those they'd rescued, her smile faded slightly. Amber had seen this before and she knew where it stemmed from. No matter what they did – no matter what they accomplished – Darien's absence had weighed on Niamh the heaviest.

She may have been a hardened veteran, but it was obvious that she missed him. They had worked together for years before Amber had even joined Blink, and now he was suddenly gone, leaving Niamh to shoulder the burden he'd carried for so long.

After a moment she sighed, then turned and trudged away, motioning them to follow with a sweep of her arm. "Come on. Let's go home."