Amber regarded the submarine with a certain amount of trepidation as the operatives filed into the Marianas facility dock. Built into the base of the facility itself, the dock spanned a circle fifty feet across that opened out into the depths of Marianas's oceans, lit by a series of globular floodlights in the ceiling. A dozen submersibles were anchored around the rim, locked in place by gangplanks: sleek prism-shaped craft studded with portholes, bobbing gently against the grey water. The one they currently approached had several station personnel scuttling around it, checking the outer airlocks and the engine pods, and loading the last of the Blink operatives' gear on board.

Walking alongside Brannigan, she glanced at the other girl and found her face to be a stoney mask, eyes locked forward. She looked like she was trying too hard not to look nervous. Despite herself, Amber felt a twinge of guilt at the way the new girl had been treated. She took a deep breath and spoke.

"So, how do you feel about going under water?" She looked over to find Brannigan giving her a quizzical look.

"What do you mean?" she asked almost accusingly.

Amber cracked a smile. "Just curious. Would be good to know where you're at before we go down there."

"A little water doesn't bother me. I grew up in a harsh environment." Brannigan's voice was firm, but there was still a slight undercurrent of nervousness in her words. Amber didn't doubt that the other operative had no fear of water, but she certainly had a fear of something. Thinking back to the mission on Titan Aquilla, Amber remembered how much it had meant to her when one of the veterans had offered to guide her – to look after her.

"I remember when I went on my first operation with these guys," she continued. "It's scary, but you'll get over it. All you have to do is keep your head. Stick close to me. I'll-,"

"Look," Brannigan interrupted sharply. "I appreciate what you're trying to do, but I don't need a shoulder to lean on. I got here on merit – I can stand on my own two feet. If you would just treat me as another operative, that'd be great." With that she quickened her pace and moved ahead, her body rigid.

Amber watched her go and felt her cheeks flush with embarrassment. Hekket moved forward into the place Brannigan had just vacated and smirked, looking at her mischievously.

"New friends?"

"Oh, belt up, Sawbones," Amber muttered, elbowing him in the ribs. He simply grinned.

When the operatives reached the sub's gangplank a willowy female in combat fatigues came bounding down to meet them. Her brown hair was tied up into a tight bun and she wore a set of gleaming tech-lenses across her eyes. Amber recognised the model. More than a visual aid, the lenses provided distance calculations, magnification variations and filters ranging from ultra-violet, infra-red, motion tracking and heat detection. Why she was wearing them at all times, Amber could only wonder at.

"Tech Sergeant Gabbi Lennox," she reeled off, shaking Darien's hand. "You call me 'Link', everyone here does. I'll be your helmswoman, technical support, communications hub and extra eye-in-the-sky – so to speak – while you're poking around down there." She made a sweeping gesture back towards the submarine. "So all aboard the Manitta-Vanna. She's a rowdy old girl but she's the fastest, toughest skimmer on the station. She can take the worst beating the seas of this little holiday destination can dish out."

"Save the sales pitch, Link," Tyndall called from the door of the submarine. "We're squared away. Our guests' equipment is stowed in the aft compartment." He glanced around for a moment. His brow furrowed and he sighed. "Where the hell is that professor?"

"Coming, Lieutenant!" a voice echoed across the docking bay. Amber looked over her shoulder to see the eccentric old man bumbling along, shorts and all, carrying nothing more than a stylus and a data pad. She caught Hekket's eye and shook her head in disbelief.

"Guess we should count ourselves lucky he can't Blink," the medic chuckled. "C'mon, let's get settled in this little cigar tube."

Amber fell into step with the others as the operatives trooped up the gangplank two by two, led on by the fizzling ball of energy that was Tech Sergeant Lennox. She found herself feeling on odd sense of limbo, as though she were both a veteran and a rookie all at the same time. Her experiences on Titan Aquilla elevated her above so many others, but she'd still only been cleared as an active operative for about six months.

She looked around at the faces of the operatives from other squads – all in and around her age – but most of them had been operatives longer than her. Part of her still felt new, and her attempts to reassure Brannigan drove home that fact. She was not yet in a position to take any kind of authority. That was Darien's place. Her place was to be – she suspected – the most precise proponent of Blink travel that the organisation possessed. There was a time she might have shied away from the label, but not anymore. Their last mission proved it not only to her squad mates, but to herself. A leader she may not be, but she could Blink like no-one else could.

To her surprise, the submarine sported bright interior lighting, with bars of white luminescence lining the roof. Only about forty feet from tip to tail, the Manitta-Vanna wasn't a large vessel by any standards, but its builders hadn't wasted an inch of space. Everywhere she looked, every wall space and crevice, there were consoles, lockers, chairs, equipment stores and gleaming screens.

They followed Link and Lieutenant Tyndall through the interior until they reached the bulbous nose of the sub, where the helm station and main control consoles were arranged in an outward-facing arc toward the thick, reinforced glass of the bridge window. The regular crew were clearly in evidence within the chamber, checking and rechecking readings as they prepared for launch.

Link loped past them and virtually vaulted into the seat at the helm, whereupon she grabbed the controls and flicked a handful of toggles with ferocious speed. After a moment of consideration she nodded her approval.

"Turbines one through four are hot – all lights are green, Lieutenant," she declared. "Equipment is loaded and all airlocks are hard-sealed. We are good to go."

"Then don't let me stop you, Sergeant," Tyndall replied. "Take us down."

"Yes, Sir." Link smiled wolfishly and punched the launch sequence into the sub's controls.

Amber felt the machine lurch and there was the briefest instant of weightlessness as the mooring clamps released their hold. Then the vessel plunged into the water, bucking up and down for a few seconds as Link made a series of minor adjustments to the controls. Foam sluiced up over the broad band of the main viewing window, and Amber could see visual displays of the underwater world being repeated on a dozen screens around the bridge, each one monitored by specialists.

Then everything went quiet.

The Manitta-Vanna sank into the depths, her forward ballast tanks dragging her down in a headlong dive. Amber's eyes flickered to the navigator's console that showed a gleaming display of the sub and its destination now slowly closing in on one and other. Then she looked back to the window and saw powerful lances of light from the sub's outer batteries searing through the grey-blue gloom.

"Destination is locked," Link said, making a minor course adjustment. "All seals are good. Estimated arrival at the staging area: twelve minutes."

"Alright everybody," Darien called, dragging all eyes of the Blink operatives to him. "That's twelve minutes for you all to check your gear and load up."

The operatives eagerly rushed to obey his command. Amber herself was almost desperate to put an end to their commute – to get away from the enclosing tube of the sub and the cramped, pent up energy of Tyndall's marines. The thrill of the unknown began to take hold. Part of her was scared, but the other part couldn't wait to be one of the first people, the first human beings to set foot in the alien world beneath the waves.

She hauled her heavy pack onto her shoulders, adjusting for the unaccustomed weight in an instant. In addition to the standard set of gear she had a belt of tools strapped around her waist in the event of any impromptu technical difficulties under the sea. She saw Brannigan fasten a similar belt around her mid-section and fumble it the first time. Amber tried not to smile as her suspicions were confirmed. The new operative's brusque manner was little more than over-compensation.

After all her standard gear was accounted for, Amber reluctantly fastened the mono-eye rig to her head. Flicking its activation switch caused a small transparent plate to slide into place over her right eye. It didn't impair her vision at all, but she could still feel it, the spindly rig clinging to her skull. It powered up, sending a small ripple of blue light through the glass. Once connected up to the main operating hub on the Manitta-Vanna everything the operatives saw would be relayed back to screens, recorded and archived instantly. Nothing would be missed.

Last but not least, she hefted the bulk of the portable Nav-Rod and slung it over one shoulder.

They trooped back through the chamber where Tyndall and the others waited. Link had changed places, now seated at a bank of computer screens manically keying in sequences.

"Okay, kids," she said. "Everyone line up – let's get the rigs calibrated."

Amber did as she was bidden, falling in alongside Niamh. She watched as the tech-sergeant punched in more commands with frightening speed. It occurred to her that maybe this frantically energetic individual might have made for a decent Blink candidate if she were a few years younger. When the sequence was ready, Link leaned back, grinned, and pressed one button. Every single screen flared into life and each one showed an imaged of the metal-plated hull of the submersible. In the bottom right corner of each display bold white letters spelled out the name of the specific operative it was connected to. Link examined the screens for a moment then looked at Lieutenant Tyndall.

"Everything looks good." She gave him a thumbs-up.

"Good." He nodded impassively then turned to stare out into the ocean. "Because we're here."

For a moment Amber was confused. It just looked like more ocean. But then the sub swung gently to the left on its predetermined course.

And they saw it.

Even the massively powerful lights of the sub could only illuminate a small portion of the mountainous structure, but Amber could see its dark mass rearing up and filling the bridge window. She couldn't stop herself from stepping closer to examine it, to drink in the ominous majesty of this foreboding place.

The exterior had weathered the worst of the sea, its burnished brass-coloured walls still glinting dully under the lights of the Manitta-Vanna. It was like a forest of metal, with clumps of buildings slowly ascending on all sides, rising and rising towards a cylindrical apex. Lights passed over colossal doors in the outer shell, each one easily a hundred metres across. The architecture was recognisable in its shape, but at the same time subtly different. The buildings formed hive-like bunches, each one shaped like a bulbous triangular prism. She could see what looked like windows studded throughout the outer shells – diamond shaped and cavernous. Everything had a geometric quality to it – lacking the artistic curves and swoops of human buildings. It captivated her.

"There she is," Professor Churchwood declared proudly. "A miracle of architecture, wouldn't you say?"

"Call it what you want," Tyndall returned. "What it is is a goldmine."

"True enough," the professor conceded.

"Navigational points for our guests are spun up," Link said, gesturing to the main display. Amber examined it, quickly memorising the size of the chamber she was soon to Blink into and the distance between it and the sub. She herself had a distance of some three thousand metres to go – a distance that would have daunted her once, but now seemed almost paltry.

"Then I believe it's time for our guests to take over." Tyndall looked pointedly at Darien, who simply inclined his head before glancing at the other squad leaders.

"No sense in wasting time," he said. "Amber, Sannick, Gale – you know what to do."

Amber nodded and strode out into the open space in the centre of the room, emotions roiling in her chest. The feeling of excitement was still building vying with a sense of foreboding. The huge dark structure was intimidating, but at the same time oddly alluring, tempting her into the unknown like the light at the end of a tunnel. She forced down the fear and let the excitement come to the fore.

It was time to write history.