The phone call with Alistair had changed the rogue agent's behaviour. Nothing from his old demeanour had been kept; the snarky comments, the flirting, even just the little sparks to ignite a conversation had vanished into thin air.

To avoid attention, I unlocked Barnes's cuffs with a warning not to run. He did not argue, did not make any sort of joke to rile me up. As my own little experiment, I left him to his own devices at one of the benches while I printed our tickets, but he did not move an inch or even talk to anyone around him.

I couldn't have that.

I sat back down beside him, tickets in hand. Spending years working with Scotty had me growing used to filling the quieter times between or during missions with pointless chatter. I'd deemed it irrelevant at first, especially during the time I did not particularly want a partner in my early days as an agent, but I longed for it now. Talking with someone I cared about filled up the empty space in my head in which dangerous thoughts darted around. I needed a substitute.

I leaned back against the bench. The station was fairly quiet for early afternoon but there was still a lot going on. A few businesswomen and men lingered in and around the coffee shop, taking calls by the door or typing away on their travel-sized laptops as they focussed every minute available on their work, fuelled by caffeine and fast-approaching deadlines. My eyes latched onto a bookstall on the side wall of the shop, gazing with longing. We were headed for a long journey, but money was scarce, needed for food, and I had no other option than to ignore my literary lust and stick to Barnes's company for the extensive hours ahead of us.

The smell drifted along the platform and met my nose. Goosebumps ran up and down my arm as my skin warmed suddenly. Not so much at the earthy scent of the coffee, or the sugary aroma of the baked goods sold along with it, but the happy memories that came flooding back. Years ago, Scotty had to drag me into a coffee shop. Now I waltzed in them as casually I would with my own flat, making the daily journey before work every morning as the two of us boarded the underground.

We didn't have that luxury anymore.

I turned away, needing something else to look at. My eyes swept through the station until they landed on Barnes. He didn't notice me looking – I had a feeling he would have said something even in this foul mood of his – and slouched with his shoulders and neck tensed, dark eyes dulling with thoughts and worries he could not snap out of.

I followed his line of sight to spy a family of four on the opposite platform. A boy stood by his father on the edge, laughing at his assumed sister as a train entered the station with a whistle and a screech of the brakes. She eyed the edge of the platform wearily, clutching her father's leg while her brother mocked her fear of falling.

Barnes's throat bobbed, and he looked away.

I still watched them. Particularly the father.

He laughed at his son but scolded him anyway. His arm stayed around the young girl, holding her close in a protective manner as if to say everything would be alright. He was there. Nothing could harm her while her dad was around. The mother watched the other members of her family from the bench behind. She knew they were safe with their father. She didn't need to intervene.

She didn't need to protect them. Not even from the man grasping onto them.

December 2005: Surrey

I never planned to go back to the lab again. Not after how my father had reacted to it the first time.

For one and a half years I had buried all remnants of the place in the back of my mind, turning away at the sight of a delivery and covering my ears with a pillow to block out any drill, scream or cry from downstairs. We lived in an isolated house a ten-minute drive from the nearest neighbourhood. No-one would have heard the sounds. No-one but me.

Then I was given an opportunity to explore and did so without a second thought of the consequences I risked putting myself through.

Marcus was out. It was parent's evening at school and, despite his lack of communication with me personally, he made a point to go. I considered offering to accompany him to get out of the house for an extra hour or two – in which Marcus was forced to be nice to me – but decided against it when he came booming up the stairs like a storm-cloud, finding me in the kitchen. I was not keen on facing his criticisms in the car, and instead told him I had a biology project to finish. He hated leaving me in the house alone, labelling my curiosity as 'a deadly curse' but knew how devoted I was to my school work, even at twelve years old. Thanks to Marcus, I had no friends to call on to distract me from it. He believed me when I told him I needed time to work on the project, and told me to behave when he snatched his keys from the wall and left for the school.

I sat down at the kitchen table, flicking through a textbook to find some form of entertainment to distract me from Marcus.

Then I was beckoned.

As I glanced at the door leading downstairs, I was struck with the sudden realisation that I was alone in the house. Father was on his way to the school, the Doctor had been and gone for the day, and the beautiful young woman I had seen occasionally rarely paid a visit. Even then, she preferred turning up in the dead of night when the house believed me to be sleeping.

I was alone. And more powerful than I ever had been since the day I was born.

He had been gone for ten minutes by the time curiosity consumed me and I went down the stairs. I calculated that, with the length of the journey there and back and the minimum amount of time elected with my teacher, I would have, at the very least, twenty minutes to explore the lab. I made the decision to return upstairs ten minutes early to make sure Marcus would not find me rummaging through his work, and to erase all ounces of guilt from my face as he arrived.

Sterile white cut through the room as all traces of metal shimmered under the dim ceiling light. Everything I could see through the shadows was clean, the air stinking of bleach and acid as my shoes stepped on the white-tiled with a squeak that made me shiver.

Marcus couldn't hear me,I reminded myself. Marcus was away.

The only strike of colour caught my eye first. Test tubes had been lined in holders on the left side of the room – dozens of them. I narrowed my eyes to read the labels on the blue, purple, red and orange liquids varying in shades and quantities: adrenaline, noradrenaline, testosterone, thyroxine – all hormones.

I didn't dare touch them.

There were others I did not recognise, but I needed to be quick. I memorised the names of a few and made a mental note to check my biology textbook when I had a spare moment alone.

I opened the glass cupboard above the test tubes to find it filled to the brim with files. I scanned a few: genetic modification, single-cell cloning, virus and bacteria, the immune system... subjects. That was the biggest folder. Subjects.

I pulled out the folder. Within it, were smaller paper folders each labelled with a number from one to twenty-four. What struck me as odd, however, was the one sticking out at the back. It was newer than most of them, the edges not crinkled or worn, but flattened and shining. I lifted the others to read the label: subject zero.

A groan made me swiftly put them back. I spun around, expecting Marcus or the Doctor, or anyone to scold me for snooping but found no-one.

I heard it again. Coming from deep within the lab.

The back of the lab turned into a corner I could not see without investigating. Swallowing my fear, I approached the shadows, touching the central table as I went by.

I startled as my finger scraped against a metal tray, upon it neatly placed surgical tools ready for use. For what, I did not know. But it did make me shudder to think about it. And pairing that thought with the screams I had heard throughout the night...

The stench hit before anything else, and I gagged as I turned the corner. It was damp and metallic, like rusting iron but mixed with vomit. I covered my mouth, eyes stinging as I fought to see the source through the darkness.

No light reached this corner of the lab, but there had to be a switch somewhere. Marcus would not abandon any resource if he thought he could utilise it, and this small space had to be no exception.

Something buzzed in front of me; a still, mute presence I could not see through the black abyss. I reached for the wall, sliding my hand across the tile to feel for a switch. I cringed as my fingers dragged through something wet and of a thick consistency, but still... warm. I cringed, and swiftly flicked on the switch as I found it.

The room spun as the shadows vanished.

Pressed up against the wall, prisoner to the ropes binding his wrists above his head, was a man around the same age as Marcus. His body drooped to one side, his head hanging low. If it was not for the faint wheezing coming from his open mouth, I would have thought him to be a hanging corpse.

Scarlet poured from his mouth in a puddle on the floor, which trailed along the tiles. It surrounded him too, smearing on the walls all the way along. I held my breath as I removed my shaking hand from the light-switch, retching at the sight of it coated in sticky, crimson blood.

Tears sprung from my eyes, the air becoming toxic as it choked me.

Marcus was a cruel man, but he was no killer. I racked my brain for anything that could justify this – any excuse to label him as anything but a madman – but found nothing. Nothing could justify this... monstrosity. No matter how much I wanted to unsee it, I couldn't. The scene in front of me was real. No amount of wishful thinking could change it.

The man gasped. I stepped back as he coughed and spluttered more blood, clamping a hand over my mouth so not to scream. His head raised meekly, and he almost seemed relieved to see me; a stranger.

"Little girl..." His voice was broken, hoarse. "Please. You have to help me."

Tears streamed down his red cheeks. A sign of weakness, Marcus had told me. Yet a grown man, a symbol of pride and strength, was begging and crying for a young girl to help him. It hurt to see how broken he was.

"How do I...?" "Just undo the ropes," he said, his voice clearer than before. I imagined he had not spoken a word for however long he had been strapped there. From the look of his beard and dying eyes, it had been a long time.

"Hurry," he ushered. "I don't know when they'll be back."

I nodded, holding my breath as my small, shaking fingers fumbled with the ropes to free him from the nightmare.

He blinked away tears and spoke, "What's your name?" he said. He was kind enough to distract me from the horror I had found, but it was of no use. Every sharp detail of the scene would appear vividly in my mind for years to come. "Amber," I croaked, biting back a whimper. The ropes had been tied tightly, the friction burning against my fingertips. "My name's Lucas," he said. I nodded as one of his wrists fell free and began work on the second, trying my best to ignore the blood dripping down his torso. He wiped his mouth with his free hand and groaned.

Then, at last, his other hand was free.

I staggered as I caught Lucas, gripping him tightly to stop him from falling. If he hit the floor, there was a risk he could not get back up again.

He sighed in relief, forcing a smile in thanks that I returned. He needed whatever reassurance he could get. "Thank you," he said.

I steadied him so he could take a practice step. I had to be quick if I was to get Lucas out of the house. Then I had to deal with Marcus. Would I phone the police? An ambulance?

"How old are you?" Lucas asked with a frown. "Twelve," I replied, watching him walk. He managed, but he had a limp in his right leg. "Twelve," he repeated. "I have a little girl at home like you. She's far younger but, still, you remind me of her."

I nodded in understanding and let him put his arm over me to walk through the lab. My stomach dropped as we passed the surgical tools on the table. Was this what they were for?

Lucas's expression darkened. "Why are you here?" he asked. "I had no idea that vicious bas—sorry, man– took kids too."

I couldn't answer – not honestly. And I didn't want to lie to a man so weak I feared for his survival. Lucas seemed to understand my silence, and managed to nod his head as if telling me not to worry about answering him.

I wanted to push for answers. What had Marcus done to him, exactly? Was there any explanation for it? What was his goal? But I could hear mother's voice in my head telling me to be kind to the man. He had gone through enough torture. My questions would only add to that.

But one way or another, I would find out what the monster I called my father was doing and stop it in any way I could.

"Girl!"

I jumped to a stop and almost let Lucas fall. I steadied him though, forcing myself to look up at the short, stout man I knew to be Doctor Arnold.

He readjusted his rounded spectacles, narrowing his poisonous green eyes in a toxic glare. I gulped, trying to gather even a slither of courage that scattered in that split second of the Doctor appearing from the shadows. "I thought your father told you never to come down here," he said through his teeth. "Now look at what you have done." I gulped. "You thought wrong." "Don't lie!" he snapped. "Your father is many things, but he is by no means a liar." His thin lips quirked. "Perhaps that is why you are so awful at it." "Your father?" gasped Lucas, quivering beside me. Oh no... "A brilliant man," said the Doctor. I bit back a curse – Lucas wouldn't trust me anymore. I wouldn't have, either. "Though," the Doctor continued, "like everyone, he has made mistakes."

A mistake. Marcus could call me whatever he wished but to my mother I was not a mistake.

I turned cold at his insult, shooting a glare at the man that instilled so much fear in me. The blue in my eyes, once soft like a calm puddle of summer rain, entwined within a wintry blizzard, glazing over in an icy sheet. To my own astonishment, the Doctor blinked, looking away from my eyes and directing his stare towards the shaking Lucas. How could I get him out now?

His voice fell so smooth from his tongue that it sent a chill down my spine. "It's a shame, really," he said through a sigh. "Doctor Knight did not want you to know about this." He glanced back at me, raising an eyebrow. "Neither of you." "Neither?" He was hardly talking about Lucas. Did he mean...? "You mean my mother?" He tutted. "Another time, girl." I swore. "You can't just say that and—!" "I can, and I will. You should learn to control your tongue. Watch your words."

I clamped my mouth shut, swallowing the pain my chest took at his warning. I squeezed Lucas's arm. He watched the Doctor with so much fear. The horrors they must have inflicted on that man... I couldn't even imagine it.

And there was nothing I could do to get him out. An exhausted, injured man and a small twelve-year-old gave little in terms of strength. We would have been helpless against the Doctor.

It was stupid to even say it. Stupider to do so with the sharp tone I held. "Let him go. Please, just look at him!" The Doctor looked him up and down with a single, lazy movement of his eyes. "I've seen worse."

Lucas let out a squeak.

"How many have been here?" I asked. "A number not of your concern," he hissed. "Fine. Then tell me what you want with them. This can't be for no reason." He scowled. "Do you believe yourself to be in a position to make demands?" "I believe myself to be in a position to question what crimes are going on in my own home."

It was bold. Too bold of me to say that. The Doctor thought so too, and apparently Lucas, who stiffened up at my words.

The Doctor shook his head and slipped his hand into the pocket of his lab coat. "You're too damn curious for your own good."

He threw his hand at me, stabbing my neck too quick for me to react. I cried at the impact, letting go of Lucas who, bless his soul, tried retaliating against the Doctor, but found all strength in his limbs dying without me holding him up.

The Doctor stood over me when my legs turned numb and I collapsed. "You should have stayed in the dark where you belong."

Sweat ran down my forehead, gasps of air turning to shallow wheezes as I hit the white tiles. All senses drifted away into nothing. The floor was no longer cold, the metallic stench had left the air. I fought to hold my eyes open but they weighed my entire face down. I blinked – I didn't know how many times – and then eventually they stayed shut.

The last thing I remembered from that day was Lucas's bloody legs being dragged back to the dark corner in which they came from. Even after waking, time from that point became a dark blur.

***

"Agent. Agent!"

I blinked rapidly as Barnes nudged my arm. He pointed to an incoming train. "Is that ours?" he asked. I nodded, still dazed as I stood. "Yes. Sorry, come on."

We found a two-person booth on the left side of the train at the beginning on the aisle, sitting opposite one another. With a sigh, I leaned against the window, closing my eyes for a brief moment. Thinking about that day in the lab... it was a lot. I hadn't thought of it in a long time – so long I almost forgot Lucas's name. But I remembered. I always remembered.

Barnes rested his elbows on the table that separated us, silenced by the rumbling of the train that rattled the furniture as it emerged from the tunnel and left the station. He opened his mouth to say something then shut it.

Movements from tracks reverberated through the glass. Through it, the station vanished into a speck as the landscape darted by. I had been sent to France on missions countless times, but never so far east. It was nice to get even a glimpse of the luscious green fields and emerald forests without worrying about catching hypothermia or passing out from exhaustion.

Dark clouds dulled their colour. What luck we had with the weather! The clear skies stuck around for all of a few hours.

I crossed one leg over the other and folded my arms. It was times like this when I wished for Scotty to be there to say something. Even just to make some pointless joke. Anything to take the thoughts away from that lab...

"Agent."

I held my arms tighter, startled.

"Are you alright?" Barnes asked. My eyes darted around the booth as I lifted my head from the uncomfortable window. "Me?" "No, the table." He forced a smile that faded when I did not reply. "You seem very down." "And you care because?"

I regretted snapping the second I did it, just as Barnes seemed to regret talking to me, which he showed by leaning back into his seat, away from me. My reaction was not needed. He was not involved in what happened with my father and taking my anger out on him was unjustified, and not okay.

"Nothing," he replied. "It doesn't—" "Wait." I was quiet, but he heard. I reached forward, mirroring Barnes's earlier posture of resting on the table. "I... I shouldn't have snapped like that. I'm sorry." Barnes leaned forward, watching my eyes as if beckoning me to answer his initial question. "I'm fine. But thank you for asking." I encouraged a pathetic vestige of a smile that seemed to satisfy him enough.

"Can we get food?" he asked with a wry grin. "And how are you going to pay for it?" I asked, lip quirking. "I have to pay? Here I was thinking that was your job!" "My job is to beat the shit out of you when I need to." "Well you're doing a fabulous job of that so far," he said with a half-smile.

I laughed in agreement, forcing myself to stop just as quick as I started. I closed my eyes for a moment and exhaled, embarrassed at the reaction, only to open them to see Barnes's grin of accomplishment shining opposite me.

He chuckled slightly. "And here I was calling you a robot."

I shook my head but did not retaliate, biting back the smile that threatened to surface again. Barnes could see it, I knew he could, but chose not to comment. Some small part of me hoped he had wanted me to speak as much as I desired him to be his old self again; that annoying yet humorous and carefree self. Shamefully, I was relieved for him to be making jokes again – a mindset Alistair would not have approved of.

If it made the mission easier to cope with, what harm was there in at least being civil with the man?

At the time I imagined there was none.