The next few panicked, scrambling minutes, fleeing further and further from safety and my friends, into the bowels of this hideous place, ranked among one of the worst experiences of my life.

Not because I was alone and scared in a unnatural place outside reality; that old fear was all too familiar. And not because of the mounting pain either, the echoes from brainmath not three hours ago, the dull ache in my diaphragm and my weak unsteady legs, no borrowed crutch for support now. Not the pervasive gloom, the way my eyes stung from squinting into the dimly-lit corridors of the ugly castle-thing, as I scurried and stumbled away from the sounds of zombies shuffling through the passageways behind me.

None of those things. The cringing void where my heart should be, that was because I didn’t know what had happened to the others.

My subconscious had convinced itself that Raine was unstoppable - if I called for her, she’d always come for me. My retreat had stalled at first, halfway down the corridor as I’d stared at the buckling door, thinking at any moment Raine would smash the zombies apart, dash their brains out, rescue me. Any moment I’d hear her calling my name, because she always comes for me.

But the zombies burst through the door and shuffled into the tight grey passages of the castle. I had to hide behind the next corner, hurry to the next turn, through the next cramped room. Raine’s name was strangled in my throat for fear of being overheard by the things pursuing me.

The last glimpses of my friends haunted my imagination, fed by the darkness and echoes. Evelyn had looked terrified, pale and panicky, eyes wide, and Twil had been buried under a pile of zombies, invincible werewolf or no. Why hadn’t Raine come for me after we’d been separated? Please, please God - I hadn’t prayed since I was a child, since before Wonderland - please let her be okay.

I couldn’t bear the thought of her injured, because to stop Raine you’d have to hurt her so very badly.

And now I was all alone. Like every Slip over the last decade of my cursed life. This hurt so much more, because I’d been with the others and now I wasn’t. I reeled and hid in the darkness, struggling to quiet my breath, trying to stay silent when I cracked a shin against a stone door frame.

I was never meant to be alone.

Not just here, in this insane misadventure, but at all, ever. I was born a twin, with another half, a mirror-image, I wasn’t made to be alone. As I was cut off from my friends and companions and my lover in this contorted trap, all I could think is that I should be dead.

Maybe it’s not like this for other twins; perhaps they don’t feel this strongly, perhaps they have separate lives and identities, instead of this gaping hole inside. I should have died without Maisie, we should have withered when apart. I wasn’t meant to be alone, I couldn’t function. I was a ghost, a phantom of half a person, and I’d spent a decade learning how to pretend I was still alive.

A few weeks, a couple of months of support and friendship, had filled the gap in my soul. And now I was alone again, and dead.

Abusive self-negation must have been some kind of survival mechanism, because eventually it cut through the panic.

I realised I hadn’t heard the zombies in a while. A minute or two maybe, I’d lost all sense of time. I stopped and sagged against the wall of a passageway, just beyond another castle room. Shaking and panting, tears drying on my face, I forced down a deep breath and pressed a hand over my heart.

I couldn’t do this. I could not do this alone. No following footsteps, but plenty of distant echoes, warped by the winding interior of the castle-thing, sinus passageways in a fleshless skull. I was inside a corpse, alone. Panic pressed in like a vice on my head and lungs. I clenched my teeth as a full-body shaking fit passed through me.

Hunkered down against the wall, I gathered a handful of the hoodie I was wearing - Raine’s hoodie, black and borrowed - shoved my nose into it and sniffed. Closed my eyes. Raine’s scent, familiar sweat. Breathed out slowly, my own breath a warm pocket under my clothes.

“Okay,” I whispered to myself, swallowed and tried again, voice shaking. “Okay, Heather. You can sit here and wait to die, or you can get back to Raine. The others too,” I added, a little guilty. “But mostly Raine.”

What would Raine do?

I wiped the tears off my face and pricked up my ears, tried to tune out the thudding of my own heart. No footsteps, nothing following me - at least, not close enough for me to hear. Had the puppet zombies retreated, or had my friends killed them all? Was Raine even now ricocheting down the corridors, calling my name, searching for me? No, I’d hear that, even twisted and distorted, even above the ever-present planetary whale song still pounding through the walls of the castle, filtered through two dozen feet of dead jade.

“Phone!” I hissed, fingers trembling in a burst of hope. Of course, Raine had her mobile phone! She’d taken it out earlier, when we’d arrived in the fog, showed it was still connected to the network, we were still in Sharrowford, technically.

Hope turned to ashes with a stabbing pang in my chest. My pockets were empty except for my notebook full of brainmath. Evelyn had handed me that before we’d left. My own phone was still sat next to my side of the bed, a million miles away in the real Sharrowford.

I resisted the impulse to curse myself and call myself an idiot, I could do that later. Instead I wet my lips and opened my mouth, Raine’s name in my throat as I stood up straight as I could - and touched the wall with my bare hand.

I flinched back, flesh crawling, biting down on the instinct to scream.

I’d thought of it as jade, as stone, even if gone grey and strangely rotten, but one brush of my hand on the material of the castle, the material of this entire pocket dimension, and I found it impossible to consider it as stone anymore.

Ossified tissue, dried insect husk, shrivelled cartilage.

I tore my eyes and my mind away from the rough surface of the wall and the dark veins inside, back to the stretch of dimly lit passageway. I wet my lips again and took a calculated risk.

“Raine!” I called, cupping a hand to my mouth. “Raine! I’m over here!”

My own voice returned a riot of echoes.

And a reply.

A howling, from a dead throat, garbled un-words from Outside, one of the demons riding along inside those zombies letting me know that it heard me. Saying hello.

“No no no no,” I whispered to myself, feet already backing away. “Raine, Raine where are you? Where are you? I can’t- I can’t-”

Another howl, a little closer.

I turned and plunged deeper into the gloom.

==

In retrospect, the chance of our group getting split up in the exact manner we were was infinitesimally small. What if I’d not fallen down, not slipped from Raine’s grip? What if I’d ducked left or right instead of retreating into that hallway? What if I’d risked self-defence via brainmath, or tried to dodge around the zombies and back toward Raine? What if I’d not thrown the bolt, not thought to run away?

When I found the tunnel leading down, I began to suspect all was not as it seemed.

I’d stumbled into the wide room half-blinded by sudden light. This room in the corpse-castle was properly lit, with tall freestanding lamps pointed at the walls, like some kind of archaeological dig site. I glanced about, heart in my throat, but the place was empty of life. Mess lay about the room - some lengths of rope and tarpaulin, a pair of jackhammers and circular blades for cutting concrete, a few power tools on a box, a discarded half-eaten sandwich in a plastic bag. That last detail made me stare in dislocated confusion; a supermarket carrier bag, in this place.

A hole dominated the centre of the floor.

Not a natural orifice in the flowing, disgusting structure of the place, but a wound, cut and pulled wide. The cultists had cut shallow stairs leading down, reinforced their tunnel with metal poles, lit it with lamps and emergency chemical glow-sticks taped to the walls.

That tunnel drew my attention like a sound on the edge of hearing, like a flicker in peripheral vision. I stared down into the open wound of dead jade.

The slow academic Heather in the back of my mind posed uncomfortable questions to the panicked exterior. What was the chance of me stumbling upon this? Of taking every correct turn in the winding passageways, like through porous bone? I could have ended up anywhere, been caught, or lost, or wandered forever.

I hadn’t been thinking on the Eye’s lessons, mapping this place with impossible mathematics. I was far too weak and exhausted for that.

Weak, exhausted, alone and scared. A vulnerable, suggestible mind.

The Sharrowford Cult had harassed and stalked me for weeks, tried to kidnap me - but I doubted they wanted me in here unsupervised, discovering their secrets alone, on my own terms. They didn’t want me to find this.

Had I been led here?

No. I swallowed and forced a deep breath, screwed my eyes shut and tried to clear my mind. That was paranoia speaking, and that way lies insanity. I was alone and needed to find my friends, we needed to beat these people, I needed to help Raine find me, and the best way to do all those things was not by lingering in a maze of twisty little passages, but by finding something important - like whatever was down this hole - and breaking it, loudly, with lots of fireworks.

That’s what Raine would do.

Pity I wasn’t good at breaking things, except myself. The discarded power tools wouldn’t offer much help, and there was no way I could carry one of the jackhammers. In the end I scurried over and found a small hand chisel among the tools. Blunt, short, pointless, barely enough to make me feel safer, but at least I had something to hand other than my notebook full of painful equations.

At the mouth of the tunnel I ripped one of the glow-sticks off the wall and hurled it down the stairs. It bounced maybe fifty feet then illuminated a sharp turn. I pulled off another and held onto it, clutched the chisel tight in my other hand, and took the first step down.

Didn’t even question the urge to descend. Should have listened to the paranoia.

The cultists’ tunnel led down in a broad spiral, low ceiling comfortable enough for me. Flakes and chips of dead grey littered the steps, little piles from drilling or sawing into the substrate to mount lamps or insert the metal bracework. It sounds so simple, walking down a set of stairs, but I had to keep a firm hand on my own barely suppressed terror, tell myself that this was the right thing to do, that my friends were not dead or in pain and I’d see them again soon. I trod as quietly as I could, every sense straining for the sounds of anybody ahead of me, so absorbed in alertness that I didn’t notice the slow change in the light until it became obvious.

After somewhere between three and five right-hand turns, the grey walls weren’t so grey anymore. The jade green began to return, as if the tunnel descended through dead outer layers to penetrate living flesh beneath.

At first a few scraps of distant green crept like buried creepers of mold. Then whole sheets flowed in frozen waves up through the dead rock, shot through with deeper, darker branching structures of viridian.

No more grey. Green, green everywhere, laced with capillaries somehow dark green and dark gold at the same time.

Inside the walls, green-gold light pulsed and flowed in bright veins.

The light stung. Any attempt to reconcile the two clashing colours together made my head hurt. I blinked and hiccuped, tried to concentrate on my feet. The light contaminated my eyes - or my brain - with after-images, ghostly alien nerve systems impressed on my sight.

At the bottom of the tunnel was a cave.

At least, that’s what I called it in my head; perhaps a biological term would be more apt. I called it a cave, so I didn’t have to think about it.

The cult’s tunnel emerged onto a sort of ridge of the jade stone-flesh, upon which they’d laid metal walkways, anchored with heavy bolts, walled off with waist-high railing and ropes and stretched tarpaulin and sacking, and lit with hooded lamps at irregular intervals. My heart juddered. I felt so very small as I crept into that vast space, cowed by the impression of great gnarled columns and spires of living jade looming in the darkness. The metal walkway snaked off between them. The walls of the cave were lost in the darkness, except for the faint pulsing of that impossible green-gold light in deep veins.

Immediately I wanted to go back, wanted to leave, wanted so very badly to not be here. Whatever was down here, I could no more break it than I could break the Eye. I was shivering all over, barely daring to breathe lest the place itself heard me.

Out of the corner of my eyes, I peeked over the railing - another mistake. The darkness went down forever. Bottomless pits are impossible, I reminded myself, but I saw impossible things with tiresome regularity.

A split-second later I squinted in confusion and realised I was wrong, the pit wasn’t bottomless. A single point of light winked down in the void, almost like a star in the night sky, the same impossible green and gold as the pulsing light in the walls.

The more I stared, the brighter it seemed, yet it stayed set in a void. How could it be so bright yet cast no illumination?

An unwelcome revelation pressed in on my mind. An uncontrollable shaking started in my lungs, spread to my hands, my breath.

“Heather!”

I jumped out of my skin - the whisper saved my sanity.

I bit down on a yelp and spun in surprise, chisel and glow-stick thrust out, as if they could protect me from anything that might lurk down here. And there she was, a little way down the metal walkway, peering around a column of dark jade.

“It’s me!” Lozzie hissed. “It’s me!”

“Lozzie!”

She scrambled toward me and launched herself into a half-tackle half-hug, heedless of the sharp object in my hands. She needn’t have worried, I’d already let the chisel fall from my numb fingers. I caught her and hung on tight, too shocked to say anything as she clung to me, too overwhelmed by the sudden shared body heat, the squirming limbs, the scent of another person. She whined low in her throat like an animal, and buried her face in my shoulder. The relief, the unbelievable relief of not being alone in this unnatural place, of finding one friend, at least.

I’d never have been able to hug her so uninhibited under any other circumstances. Right now I was so glad to see anybody I could have cried.

After a moment we both pulled apart, as if by mutual agreement. Lozzie held onto my hands and swung our arms together from side-to-side, like we were a pair of schoolgirls standing in a playground. She lit up in a huge smile.

“I found you! I really found you! Are you okay, did you get hurt? You didn’t get hurt, did you? Where are all- all your friends? You’re alone now, okay, that’s not good, but we can work with it, we can fix that.” She vomited up a torrent of words, breath shaking as she spoke, nodding and rocking, then caught herself and almost giggled, lowered her tone to a whisper. “You really shouldn’t be down here, Heather. It’s super super not safe. I’m actually really scared right now even if I don’t seem it, you know?” Her smile quivered as she bit her lower lip.

The real Lozzie was not as perfect as her projected dream-self.

She was greasy and unwashed, though I didn’t give a damn about that right now. I probably still smelled of sweat and vomit myself. Her nails and cuticles were chewed to ragged stubs, dotted with little scabs. She wore two long sleeved tshirts one over the other, and a pair of old pajama bottoms, her feet bare, toes curled against the cold of the metal walkway. Her endless wispy hair was a matted mess and a livid bruise marked her face where her brother had hit her earlier. She looked borderline malnourished, too thin and pale, a half-starved teenager held together with manic twitchy energy.

She had something wrong with her eyes - her lazy, heavy-lidded look from our shared dreams was held in reserve behind panic and fear, but it was still present, a slackness in her extraocular muscles.

Guess I hadn’t been entirely myself in the dreams either.

“You’re … ” I trailed off, overwhelmed by the solidity and physicality of her. I squeezed her hands, stopped her swinging our joined arms. “You’re real. You are real. Okay.”

“Ahh? Heather?” She blinked at me and tilted her head rapidly from side to side. “Of course I’m real? What are you talking about? Don’t be silly, not now, we’re in a seriously scary place!”

It was her. No doubt about it. The same fey, elfin little face, underneath the fear and the abuse. I could worry about dreams later, Lozzie was here and now, with me, in this, together. I needed to deal with it.

She had blood in her teeth.

“Lozzie, are you bleeding?”

“What? Oh.” She suppressed a mad giggle, a glint in her eyes. “Had to bite somebody to get away.”

“You- okay.”

“Don’t look so surprised! I had to! Oh, don’t judge me, please, I had to. Not you, Heather, not-”

“I’m not, I’m not,” I stammered out in a whisper. “There’s just- there’s a lot to deal with right now. I thought you’d been hurt, that’s all.”

“I have been,” she said with a strange gulp, then her expression crumpled into tears, cringing, small. “I thought you’d been hurt too! Oh, Heather, I’m so sorry, I had to do it, I couldn’t- couldn’t say no- but I gave you that back door, and- and- nobody got hurt, right? Please don’t hate me, please.”

“I don’t, I don’t,” I said, and I meant it. We hugged again, by shared impulse. “It worked, I came to find you. It worked.”

She sniffed, wiped her face on her sleeve. We parted again and she smiled once more, a little more broken than before.

“What did you mean, I’m real?”

I couldn’t stop myself from giving her a bit of a look, despite the circumstances. “You didn’t exactly make it easy to believe that at first. Why the dreams? Why not … I don’t know, call me or come visit or … ” I trailed off as I realised my own idiocy, and began to stammer an apology. Lozzie just shook her head, a sad smile on her face.

“They don’t let me out very often. I learned about you from the messenger your sister sent - all about you! I knew we were the same, we could be friends, I knew you might, you know, be able to help me.”

“My … my sister … a- has- had, a message? Yes, right.”

Even now, in the middle of a crisis, outside reality in the core of some unspeakable corpse-nest, whispering to avoid the attentions of that blinking star in the deep, those words needled my heart.

“Yeah!” Lozzie hissed. “For you. Like, it wasn’t words but it wasn’t hard to figure out. Don’t you remember-”

“Why didn’t you tell me?!” I hissed at her. Lozzie blinked and recoiled, a startled fox. “It was- from Maisie, I-”

“I did! I did!” Her hands went up. “You don’t remember? It was the first thing we ever talked about in the dream. I told you. She needs help. She was asking for help. Like me.”

“Like- … ” I opened my mouth, closed it again, gently took her hands. She let me. “I’m sorry. I’m sorry, Lozzie. When you- with the Messenger, in that underground car park- I … I thought you were stealing the message from me. It hurts to think about my sister. I can’t talk about this now, not here. It’s not the time to talk about this.” I risked a glance up and around, at the cave. “Is it?”

Lozzie shook her head, then nodded - I found the dual gesture so endearing that in any other time and place it would have made me laugh. “Leaving is a very good plan, yes!” she hissed. “Make like a tree and split!”

“Of course. Absolutely. So how do we get out? Brainmath teleport doesn’t work from in here, right?”

“Brainmath?” Lozzie hitched an eyebrow. I tapped the side of my head.

“The thinking magic. Sorry, that’s what I’ve been calling it. The math.”

Lozzie stared, sniffed and rubbed her nose, winced at the bruise on her face. “It’s not maths for me. But yes, yes, no happy jumping from inside the scab. That’s why they keep me here. I ran away from home once and when I came back - click click, wheee.” She made a locking gesture and threw away an imaginary key. “They had me on a leash when I saw your twin’s messenger, you know?”

“Scab?” I echoed.

“This place, yeah. It’s a scab. Long story. A proper long story that you tell at night with hot chocolate and a nice view of the stars - not here. Not where it can hear.” She nodded over the side of the railing, into the depths.

I glanced down without thinking, at the star in the void. Lozzie put her hand up to my face, blocked my view.

“Best not to,” she said, a manic shaky smile on her face. “It won’t feel very good if you pay too much attention to it.”

I swallowed, throat dry, took Lozzie’s hand and lowered it from my face. “Okay. Thank you. Okay. So … what do we do? We have to get back to my friends.”

“Did you kill my brother?”

“Um, not yet.”

Lozzie bit her lower lip, hard, eyes creasing with worry.

“Raine might,” I said.

“She’s the one who said I should jump, yeah? I liked that. Clever!”

“She is. And brave. And-” I swallowed. “Oh God, I hope she’s okay.”

Lozzie squeezed my hand. “She’ll be fine, I’m sure she will. She’s like, chief arse-kicker, isn’t she?”

I nodded. “She’s got a gun, too. It-”

“Didn’t work on him!”

“Yes, we discovered that. Evee’s here too, she’s a magician. And Twil, she’s a werewolf. They must be able to do something to him.”

Lozzie blinked at me. “Werewolves are real?”

“I know. Stupid, isn’t it?”

“Are you kidding? That’s so cool. I love it!”

I swallowed, unable to share her amusement. “I’m so worried about them. We got cut off, I- I’m no good on my own. I don’t know what to do.” I looked over my shoulder, at the way I’d come. “The way back is full of zombies, I couldn’t get back to Raine.”

Lozzie peered over my shoulder too, then bit her lip and looked up at the distant ceiling, lost in the darkness.

“What does your brother - the cult - what is it they want with me?” I asked, unable to bear the silence.

“Hmm?” Lozzie met my eyes, seemingly distracted. “Because you’re like me. All he’s done for years is try to make more of me.” She glanced back the way she’d came, half turning on the spot and chewing on the stub of a fingernail. “We could go back through the underground, but … don’t look down at it, okay? And try not to listen. Stay close, okay? It’s really good at getting inside your head and making you think you want to listen.” Lozzie shot me another shaky smile, then tugged on my hand to lead us deeper into the cave.

“Don’t listen? To what?” I whispered.

“My brother already hurt it earlier,” Lozzie muttered, a sad pinch in her voice. “When he set it on you and your friends outside the castle. It’s hurting a lot now, it needs somebody to listen, but we really, really shouldn’t. Try not to, okay? Try not to.”

==

Perhaps it seems strange that I would so readily trust a person I’d met in a dream. A vestigial part of myself, cradled in my heart, asked again and again if this wasn’t a symptom of insanity. Wasn’t this the exact behaviour I was supposed to watch myself for? That I’d spent years punishing myself for, terrified that at any moment I might slip over the edge, talk to people who weren’t there, scream at invisible monsters, retreat into a world of my own imagination?

That part of me was obsolete now, proved wrong, but I didn’t shout it down or bottle it up; I soothed that terrified, battered part of myself. It was okay, her watch was over, and now I had to be brave in a very different manner.

Being brave wasn’t easy in this place.

I’d never been in a cave before. Not exactly a good family day out for a girl with schizophrenia and night terrors. I clung hard to my initial sense of this place as a cave, a natural formation in rock. Geology - not biology, no matter the impression of organic structure in all the looming shapes in the darkness.

Lozzie and I held hands as she led us creeping back along the metal walkways. The pulsing green-gold light lent her face a sickly, contagious pallor, turning her into a half-starved plague ghost. I must have looked terrible too, twitchy and frightened and doing a bad job of hiding my fear. We made quite the horror-movie couple, a pair of scrawny, unhealthy apparitions one might encounter in a dark, forbidden place.

Lozzie paused before each turn, each corner around another projecting spar of living jade. She held her finger to her lips, craning up on tiptoes and peering around rock outcrops.

The first time she did this, I whispered as quietly as I could, “Is anyone down here?”

“Doubt it,” she hissed, and shot me a mad smile over her shoulder, half-hidden behind the sleeve of her filthy tshirt. “Lost them all upstairs, but a zombie might wander down. Nobody else would be stupid enough - not like us!”

I trusted her completely, not in spite of her obvious mental illness - I could recognise that now, with the clarity of my waking mind - but because of it.

We’d been together in far worse, far weirder places than this, by choice and for the sheer joy of fascination, but always cushioned by the dream logic. Always with the knowledge that if anything really went wrong, we could simply join hands and leave, go somewhere else. Now we were in it for real, truly together.

The cult’s pathway branched several times, vanishing into unlit dead-ends or unfinished drops onto the jade substrate itself. We passed a gigantic branching stalagmite of green-gold glowing rock, a monolithic tree in the heart of the cave, and I spotted a wide metal platform far ahead of us.

Wedged underneath a convenient overhang of rock, on the platform stood structures I couldn’t quite make out at this distance - a few tables perhaps, bundles of rags, tools and debris and-

“Lozzie,” I murmured, squinting. “Up ahead, are those … cages?”

“Yeah!” she hissed. She must have caught my expression in the corner of her eye, because she turned to me and smiled that shaking smile again. “Oh, it’s totally okay, you don’t have to look at them. Just concentrate on your feet when we pass by, yeah? Or look at me.”

“What?” I said in an empty whisper.

“It’s fine, it’s fine, I’m our eyes right now. Okay? I’ll navigate.”

No courage to push the question, but neither could I look away from the cages up ahead. Six foot cubes of steel mesh. Dog cages?

Lozzie tugged on my hand. “You don’t have to look!”

Don’t look up, don’t look down, don’t look at what was right in front of me; I began to feel a little like Perseus in the Gorgon’s lair.

The act of thinking about it - the core of this place - drew my eyes over the side of the railing, to glance at the shining star-thing in the void below.

We seemed closer to it somehow. No longer a point of light, I saw - or imagined I saw - a faint impression of roiling energy through a gap in a cracked shell. I still held the glow-stick in my free hand, and suddenly felt the most bizarre urge to toss it over the railing, so the falling light might reveal the smallest fraction of the true shape below.

“Heather, Heather? Hey, no no, here here!” Lozzie touched my face, brought me back up and around. I drew in a sudden deep breath and blinked at her frowning face.

“Oh, that was weird. I was-”

“You mustn’t let it distract you. It’s really good at that. I don’t blame it, it’s lonely and mad and in pain, but you mustn’t listen - you’re too good, Heather. You’re too good a person, too kind, too nice. Don’t let it talk.”

“O-okay, okay.” I took another deep breath and shoved the glow-stick into my pocket. “I’m really … it’s hard to think clearly right now, that’s all.”

“Talk to me then! We’ll drown it out together.”

Lozzie beamed at me as she dragged me onward. The metal platform lay only a few hundred meters ahead now. I struggled for the words to distract myself.

“Um, well, why the goat skull mask? What was that all about? When I first saw you, I mean.”

“It’s a skull!” Lozzie almost giggled. “It looked super cool. Plus nobody can tell where I’m looking when I have it on. I like masks.”

“You- oh!” I lit up inside, a genuine moment breaking through. “You sent Tenny, didn’t you? That was you. You sent her to help me.”

“Tenny?”

“The spirit with the tentacles. Thank you. I never thanked you for that, in the dreams or anything. She used your name once, even. I get the feeling she wasn’t supposed to give that away, but thank you. She saved me, weeks ago, it’s kind of a long story.”

Lozzie paused and blinked at me. “Oh, that.” She frowned softly. “I made that from spare parts, I totally didn’t think it would find you. Wow!”

“I’m sorry, you made it? You can do that?”

“Yeah. Can’t you?” Lozzie looked at me with a mystified expression, tilting her head to one side, as if we were talking about baking a cake rather than constructing a spirit monster.

“I don’t think so … ” I trailed off and swallowed. This wasn’t the time. I had to focus on getting back to Raine, getting out of here. I had to focus on the here and now.

On the platform ahead of us the cages were clustered at the rear, against the jade rockface.

Too late to take Lozzie’s advice now. By the time we stepped onto the platform, I was already staring. Couldn’t look away, a far stronger pull than the thing in the void under our feet. The cages, the bundles of rags within, the table, all sharpened into too-perfect clarity on the surface of my mind. My insides went numb.

“You don’t have to look, Heather! Come on!” Lozzie’s raised voice warped into distorted echo. My feet stuttered to a halt. She pulled on my arm, both hands around my wrist, tugging on my sleeve. “Look at me, focus on me!”

“Lozzie, stop!” I snapped, and winced at the echo of my own shout, shaking off her grip. I glanced at her stricken expression and back at the cages, my breath tight in my chest. “What is this?”

“They’re dead. They can’t feel anything anymore. We can! Don’t worry about them, okay?”

“Worry?” I almost spat, shaking my head. “I- … ”

“Don’t think about it, okay? Off, off!” Lozzie waved her arm in the air, as if trying to shoo away a flock of birds. She screwed her eyes shut. “Out of sight, out of mind!”

I ignored her, only half by choice, and tried to comprehend what I was looking at.

The platform in the depths was not a big place. Not grand, except for the surroundings of the vast cave. At one end of the platform a stout metal table faced the void, complete with restraints to hold a person and channels to collect spilt blood. It was covered in dark stains. A helmet made of copper was anchored to the head of the table, and inside I could see little patches of scalp and burned hair. A thick cable of bare copper and woven rope descended from the helmet, led off the side of the platform, into the void below. A triple-layered magic circle in stark clean white ringed the table, surrounded by the ghost images of dozens upon dozens of old, partially erased circles.

A shrivelled twist of cooked gristle lay atop the table, like a piece of meat left too long over a fire, no larger than a cat.

The cages were full of corpses.

Perhaps a dozen, if I could have counted. Dried, dessicated, preserved from rot by some quality in the air. Some were bound and gagged in death, others curled up and shrunken. One had gnawed off his own fingers - I doubted rats were responsible, down here. Several had their eyes bandaged as if blind, the dressings caked with dried blood, the faintest green-gold glow showing through the fabric. All were lumpy and misshapen under their filthy clothes, as if changed in hidden ways. None could have been older than twenty. Several were small children.

Lozzie spoke, waved her arms about, grabbed my hand, but I didn’t really hear her.

I wasn’t surprised. I’d seen the prelude to this discovery, the zombies made from kidnapped homeless people, the ape demon impaled outside the castle as a warning. The fruit of cruelty.

I’d never seen evil before. The Eye wasn’t evil - it was alien. Despite everything it had done to me, to my sister, despite the torture of having my mind altered, my reality bent and broken, the Eye was not evil. The star in the void wasn’t evil either, nor were the nightmare spirits I saw every day of my life, nor the inhabitants of the hundred Outside places I’d been to.

This little space, this thing done by people, this was evil.

This filthy secret, this felt like the centre of what the Sharrowford Cult was doing.

I didn’t need to be a genius to connect the dots; the corpses to the table, the helmet, the cable dropping into the depths, down to that thing in the void.

Forced communion.

“- and if you dwell on it, it’ll eat you up, it’ll take every piece of-”

“Can we destroy this?” I interrupted Lozzie’s rambling, swallowed, forced myself to feel and move again. I looked right into her heavy-lidded eyes. She juddered to a halt and blinked at me, then sketched a shaky smile and nodded sideways into the pit.

“We’d have to kill that down there,” she said. “This stuff’s just stuff.”

“How? How?” I glanced down into the void, then pulled my eyes back to Lozzie. It was easier, with this coldness inside me. “How?”

She shrugged. A laugh jerked out of her mouth. “I don’t know. A nuclear bomb? A- a- a god? Drop god on it. Right. That’ll work.”

“Point taken.” I squeezed my eyes shut. “I’m sorry.”

“It’s okay. It’s okay.” She swallowed and sniffed, eyes twitching and flickering over all the evidence she’d tried so hard to get me to ignore.

“Maybe Evelyn can stop it. She’s a magician,” I muttered, more to myself than Lozzie. “I have to tell her. Lozzie, what is this, what’s it for? How do we break it?”

She shrugged. “I don’t know! I’m the only one it ever worked on.”

“W-what? You mean-”

“You can’t just rape it and expect it to give you a piece of its mind. They can’t make another me, because they just wanna take and take and take and there’s nothing left down there, it gave me all it had.” She screwed a finger against the side of her skull. “It was a present, a gift, a- a- all it had. You get it, right?”

I stared at her, horror building on horror. But I nodded. “Yes. Yes, I think so.”

“I wish we could kill it.” She sniffed, tears in her eyes. “Put it out of it’s misery.”

“Maybe there’s a way. Maybe Evelyn knows a way. Maybe we can-”

A silent blur launched itself up and over the side of the platform railing.

Lozzie and I both screamed and jumped, grabbing at each other like small frightened animals about to clamber over themselves to get away. A heavy hand twisted against the railing, a long coat whipped through the air. Boots hit the metal in front of us.

Zheng landed on the platform with all the grace of a drunken elephant.

Her left side was still soaked with crimson, half-dried into a sticky layer down her coat and trousers and all over her boots. Her left arm - the one I’d torn off - had completed the disgusting reattachment process we’d witnessed earlier in the fog labyrinth. It hung slack at her side, naked and covered in a winding mass of occult tattoos so dense they turned her pale flesh to almost solid black. Her shoulder wound formed an angry jagged expanse of pulped, re-knitting flesh.

Seven feet of zombie muscle straightened up, cracked her neck, and turned dead eyes on Lozzie and I.

She was all there.

For the first time ever, I reached for the hyperdimensional mathematics without even thinking.

Maybe it was the memory of her grabbing my face and holding me immobile, maybe the shock of her dramatic entrance, or maybe I was finally turning into something beyond human. I grabbed at the impossible equations held so gingerly in the back of my mind, broke the seals, clenched my teeth as I spun the numbers into place, each lever of reality tar-slick and burning white-hot inside my brain. Knock her clean off the platform, burst her skull, blast her into steaming meat - could I do any of that?

I could. In that moment of panic, I knew I could.

Might kill me, but I could.

I sagged in Lozzie’s grip, my head and guts on fire, half a second away from an equation to rip reality asunder.