As it reached the base of the great crystals, they too changed. Black scales turned grey, then flaked and crumbled, stress fractures stabbing upwards through the dark spires. One spar, angling almost horizontally from the surface until it hit the cavern’s far wall, collapsed into the lake of ooze with a thunderous boom. Whatever else Thor’s Hammer was doing to the eitr, it was clearly also affecting the crystals that had grown from it, removing the slight flexibility in their structure that had allowed them to curl and zigzag up the shaft like serpents – and without it, the huge natural formations were unable to support their own weight.

  More crystals splintered with gunfire cracks as the discoloration seeped upwards. Eddie saw that his position was more dangerous than ever, any doubts disappearing when one of the light globes floating on the eitr ruptured as the sizzling froth ate through it. ‘Oh, fuckeration!’ he yelped, jumping back from the lake’s edge as it crumbled and sank into the slime.

  He ran for the crystal that Lock had used to make his ascent, hoping it would survive long enough for him to follow the American’s route upwards – but swerved as he spotted his Wildey. The rubble beneath it was being eaten away by the chemical reaction spreading through the eitr, and the toxic substance was surging up from below, about to swallow the weapon—

  Eddie snatched up the gun just before the liquid claimed it. ‘No you fucking don’t!’ he gasped, changing course back to his escape route and pounding up it as fast as he dared. The span shifted under his weight, pieces shearing away where it scraped against other crystals below it.

  Nina made an awkward landing, having to drop to all fours to keep her balance on the crystal bridge. She gripped it for a few seconds until she had stabilised, then looked down to locate Lock and the eitr canister.

  The latter was still swaying from the jutting black spike, the green LED glowing. Lock was below it, standing on another span and reaching up for his prize—

  Still on her knees, she lunged just as he clamped his hands around the sides of the cylinder and jerked it upwards to flick it free. She grabbed the strap as it fell away – but was now caught in a tug of war against a much stronger and heavier opponent. And Lock had secure footing, while she was unbalanced, arms outstretched as she struggled to keep her knees on the crossing’s upper facet. She pulled as hard as she could, trying to snatch the canister from Lock’s grip . . .

  It wasn’t enough.

  A sharp yank from below tipped her forward – and for the second time in mere minutes an awful shock of fear slammed her heart as she fell.

  She screamed – only for it to be cut off as she slammed to a joint-straining halt.

  The strap had caught again, this time over the top of a cluster of larger spikes stabbing out from the flank of the crystalline span. They creaked alarmingly, black turning almost to white as fracture lines formed, but held firm. She was dangling just a couple of feet from Lock, but while he was standing firm on the narrow crossing, there was nothing below her except the now-seething surface of the eitr lake. Eddie must have used Thor’s Hammer, she told herself as she glanced down, but that gave her neither help nor comfort.

  She looked back at Lock. He was still gripping the inverted canister with both raised hands, but with Nina’s entire weight now pulling against it was straining to keep his hold on the slick metal. If he let go, Nina would drop to her death – but he would also lose the eitr sample.

  If he leaned across to kick Nina loose, however, the container would drop neatly back into his arms as she fell . . .

  Lock had realised this too. His knuckles whitened as he tightened his grip on the stainless-steel cylinder, then he hesitantly lifted one leg to check that he could maintain his balance – before lashing out.

  The toe of his boot hit Nina’s calf. She imprisoned a cry behind clenched teeth, squeezing her hands more tightly around the strap. Another blow, this one less painful, but Lock was already lining up for a third strike. She looked up. The strap was bunched up in her grasp. She jerked one hand, clamping it back around the tough woven nylon and pulling herself upwards by a few inches.

  Lock redirected his attack as Nina dragged herself up by another palm’s-width. His boot cracked viciously against her ankle, her own sturdy Arctic footwear saving her from an agonising injury. Even so, she still squealed in pain as she dragged herself higher once more.

  ‘God damn it, woman, you don’t know when you’re beaten,’ he growled. ‘Just give it up!’ He struck again, this time landing a solid hit on her shin. Nina shrieked, the muscles in her hands burning as she clutched her lifeline. ‘The eitr’s mine!’

  He pulled back his leg for the last time—

  Nina strained to pull herself another few inches up the strap – and to Lock’s surprise let go with one hand. ‘You want it?’ she gasped, stretching out her arm towards the eitr canister. ‘Take it!’

  She jabbed her forefinger at the latch button. There was a click, the green LED turning red . . .

  The lid released.

  ‘No!’ Lock cried – then his voice became a gargling scream as the container’s deadly contents gushed over his face, his skin blistering and his nostrils and mouth filling with the black poison. He thrashed in mindless agony, globules of eitr flying from his dissolving flesh—

  One of them hit Nina’s left cheek.

  It was only the tiniest drop, but it still felt as if she had been stabbed by a red-hot needle. A new terror filled her as she realised what had happened – but she had no time to react as Lock let go of the now empty container.

  She plunged—

  Strong hands seized her wrist.

  ‘Gotcha!’ Eddie yelled.

  Lock let out a final choking wail. Most of the eitr had now run off his face, exposing the ruination it had wrought. Both his eyes were gone, black-tainted blood oozing from their sockets where the caustic toxin had dissolved the soft tissue. The flesh on his cheeks had almost liquefied to expose teeth and bone beneath. Bubbles gurgled from his throat . . . then he keeled over, tumbling back down the shaft to hit the seething froth filling the bottom of the cavern with a sizzling splash.

  Eddie hauled Nina up, her feet gratefully finding purchase. ‘You okay?’

  ‘Yeah, but—’

  ‘Great, now fucking run!’ He hurried up the slope, pulling her behind him. ‘Kagan’s goop worked, but all the fucking crystals are melting! They’re going to collapse!’

  She looked down – and wished she hadn’t as she saw a wave of diseased grey seeping up the crystalline pillars after them like ink through tissue paper. The smaller spars within the cavern were already breaking apart and falling back into the lake; the thicker structures snaking towards the surface could not be far behind.

  A nightmare ascent followed. Every step was a strain as the pair clambered up the steep spans, switchbacking from one side of the shaft to the other as they hunted for navigable routes through the vertical maze. Nina spotted Berkeley’s body as they passed, but there was no time to acknowledge his redemption and sacrifice.

  Instead, she followed Eddie upwards, climbing and jumping between the crystal bridges. The cracks and booms from below grew ever louder as more of the eitr formations were destroyed by Thor’s Hammer. Fractures scythed through the crystals around them—

  Eddie abruptly stopped and shoved Nina against the rock wall, shielding her with his own body as one of the thinner of the great serpents disintegrated and plummeted past them, cascading debris smashing crossings as it fell. He looked up to see that the collapse had torn away almost a quarter of the winding pathways above. ‘Shit! If another one goes like that, we’ll never reach the top!’

  ‘I can see the ropes,’ Nina said, narrowing her eyes against the glare of the sky. They were about fifty feet from the lip of the shaft, the lines placed by Lock’s team dangling over its edge.

  Eddie scanned their surroundings. ‘That way,’ he said, pointing at one of the surviving crystals. They made their way around a ledge, then scrambled up. The span tremble
d underfoot, echoing snaps reaching them from below as more spires crumbled. ‘Nearly there!’

  They leapt across a gap to the final span, the ropes hanging tantalisingly above its top. Escape was in sight, but now Nina remembered that there was another danger waiting for them. ‘How long before the missile gets here?’

  Eddie glanced at his watch. ‘Fuck! Two minutes, if that!’

  ‘You’re faster than me – get to the radio and tell the Russians. Don’t worry about me.’

  ‘Sorry, love, but that’s my job!’ He reached the ropes, then stopped and waited for her to catch up. ‘Come on, come on!’ he said, holding one out to her. ‘Grab it, quick! The crystal’s about to—’

  A colossal boom came from far below.

  Nina dived, grabbing the rope—

  The remaining crystals lurched, then plunged down the shaft in unison as their corroded bases finally gave way, breaking apart as they smashed against each other. Even the sections that had spiralled up the walls and bonded with the blackened stone were scoured away by the falling debris, leaving only a vertical drop into the bowels of the earth.

  Long seconds passed before the pounding clamour finally began to fade. Dust swirled around the shaft . . . and then, coughing, two figures painfully dragged themselves up the ropes on to the steep incline above. ‘Oh my God,’ gasped Nina. She wanted nothing more than to sit down and rest, but knew she had to keep going. ‘Are you all right?’

  ‘I’ll live – but only for about a minute if we don’t call Moscow,’ Eddie replied, grimly hauling himself onwards. The slope became shallower. They let go of the ropes and ran for the surface, feet like lead. ‘You know,’ he gasped as they scrambled up the final few yards, ‘if Tova’s got any sense, she’ll have buggered off in the chopper already.’

  ‘Yeah, but I hope she left us the radio,’ said Nina. The lip of the pit came into view as they both emerged into the light, the snow-topped runestone beyond. A gap had opened in the clouds, weak sunlight finding its way through, but her eyes were locked on the nearby helicopter. ‘Thank God! Tova!’

  Eddie ran ahead of her. ‘Radio!’ he yelled as Tova peered out of a cabin window. He waved furiously for her to open the hatch. ‘Radio, radio! Radioradioradio!’

  She opened the door and jumped out, the gun still in one hand – and Kagan’s satellite transmitter in the other. ‘Eddie, Nina! What happened!’

  ‘Just turn on the radio!’ the Englishman shouted as he pounded through the snow. By the time he reached her, she had done so. He snatched the unit from her. ‘Hello, hello!’ he said into it. ‘Can you hear me? It’s Eddie Chase – we used Thor’s Hammer, we’ve neutralised the eitr! Abort the missile!’

  Nothing for a few seconds, then a voice replied – in Russian. ‘What the hell’s he saying?’ panted Nina as she arrived.

  ‘I dunno!’ Eddie turned to Tova. ‘Do you?’ She shook her head. ‘For fuck’s sake! English, nyet Russkie!’ he told the radio. ‘Abort! Abortski!’

  His wife clutched his sleeve. ‘Uh, Eddie . . .’

  ‘What— Oh, fuck.’ He looked around to see a small black dot against the grey clouds to the north-east.

  Small . . . but growing.

  ‘It’s the missile,’ Nina said in disbelief. ‘Oh God, it’s here!’

  Eddie tried the radio again. ‘English, English! Er . . . Anglijski!’ he said, dredging up something from his limited knowledge of the Russian language. ‘Speak bloody English, and abort the missile!’

  Nina held him tighter. ‘It’s too late.’ The dot was still growing. A faint jet-engine shrill became audible over the wind. She exchanged a last look with her husband. ‘Eddie, I love—’

  The missile suddenly angled steeply upwards, disappearing into the overhanging cloud layer. ‘What happened? Where’s it going?’ she asked.

  ‘They aborted it!’ Tova cried with an astonished smile.

  Eddie’s expression told Nina that was not the case. ‘It’s going up – so it can drop straight back down into the hole.’ As if in response, the missile reappeared through the gash in the clouds as it kept climbing . . . then reached the top of its arc and rolled over to make a final plunge to earth.

  He shouted into the radio once more, gripping it so tightly that its casing creaked. ‘The eitr’s been neutralised, Thor’s Hammer worked – I repeat, Thor’s Hammer worked! Abort the missile!’ The cruise began its vertical descent. ‘Abort the missile! Jesus Christ, abort the fucking missile! Come on, you stupid beetroot-eating bastards, abort—’

  The pale grey pencil of the Kh-102 rocketed towards them—

  And exploded.

  Nina shrieked, thinking that the nuclear warhead had detonated – then realised that if it had, she would not still be there to have the thought. ‘Whoa, cover!’ Eddie yelped, grabbing both women and pulling them against the helicopter’s fuselage as smoking debris showered over the plateau.

  The missile’s burning engine and warhead, the heaviest parts of the weapon, continued on their final course and plunged into the opening. Further crashes and explosions echoed up from below as they hit the collapsing remains of the serpentine crystal pillars.

  Smaller chunks of debris smacked into the chopper, denting aluminium and cracking Perspex. Then the metal hail stopped, the explosion’s echoes fading to leave only the ever-present moan of the wind.

  The Englishman peered cautiously at the pit. Dark smoke had replaced the pale steam rising from the gash in the earth. ‘Buggeration and, well, you know,’ he said, moving into the open. ‘That was too bloody close.’

  Tova gazed wide-eyed at the scene. ‘Is it safe? The nuclear bomb – if it exploded, won’t it . . .’

  ‘We’re okay,’ Eddie assured her. ‘The missile blew up, not the warhead. It’s down in the pit somewhere – hopefully at the bottom of a big pool of slime where nobody can dig it up.’

  ‘And what about the eitr? Did Thor’s Hammer work?’

  ‘Yeah.’ He gave the Swede a smile. ‘Ragnarök’s cancelled. We killed your Midgard Serpent, and didn’t even get poisoned by it. So we came out of it better than Thor. Didn’t we, love?’

  He addressed that last to his wife, but got no answer. ‘Nina?’ he said, looking back at her.

  Her face was turned slightly away from him. There was no relief or triumph in her expression, just a stricken horror. ‘Eddie, we . . . we didn’t get all of the eitr.’

  He moved closer, feeling a rising sense of dread even without knowing why. He had never seen such a look on her face before – but he had seen it on others, in combat. It was the realisation of the trapped, of the wounded . . . of someone who knew they were going to die. ‘Nina,’ he said, now fearful. ‘What is it?’

  Nina looked straight at him. On the pale skin of her left cheek was revealed a small red mark, as if she had been burned by a flying ember.

  But there had been no fires in the pit.

  Her voice quavered as she spoke. ‘When I poured out Lock’s eitr—’

  ‘No, don’t,’ Eddie begged her. If she didn’t say the words, it might not have happened . . .

  But she continued, tears swelling in her eyes. ‘I got . . . I got splashed. It was only a drop, but . . . oh, God.’ What remained of her resolve crumbled. ‘Oh my God,’ she gasped, her voice breaking.

  Eddie moved closer, but Nina backed off, turning her reddened cheek away from him. ‘Don’t touch me,’ she whispered. ‘There could be more of it on me, I might be . . . contaminated.’

  He reached out, desperate to comfort her, to feel her skin – but stopped short, letting his shaking hand slowly fall. ‘Nina . . .’

  ‘We need to get out of here,’ she forced herself to say through her tears. She opened the helicopter’s hatch and climbed inside.

  Eddie stared after her, for a long moment unable to move. Tova spoke, but he didn’t register her words. ‘I’m fine. Let’s go,’ he said in gruff automatic reply, taking the gun from her and stepping away to let her board the aircraft.

 
Hoyt’s mocking words returned to him. Just can’t protect your women, can you, Chase?

  He looked back at the pit – then emptied the weapon at the sneering ghosts above it with a roar of fury and despair.

  Epilogue

  New York City

  Oswald Seretse regarded the letter on his desk with solemn dismay. ‘Are you absolutely sure this is what you want to do, Nina?’

  She had to compose herself before replying, emotions churning beneath her outward calm. ‘Yes, I’m afraid so. That’s my resignation from the IHA, effective immediately.’

  ‘Mine too,’ Eddie added curtly from a chair in the corner of the official’s office.

  ‘But why?’ Seretse asked. ‘You haven’t given me a reason.’

  ‘Do I need to?’ said Nina.

  ‘No, but—’

  ‘Then can you please respect my decision?’ He was taken aback by her hard tone; she softened it in apology. ‘Believe me, if the circumstances were different I wouldn’t be leaving. But . . . I have to. There are other things I want to do – need to do.’

  ‘Such as writing your book?’

  She was a little surprised. ‘You heard about that?’

  ‘Having my own office at the UN does not isolate me from the latest gossip. And I would be a poor diplomat if I did not keep my ear to the ground.’

  ‘I guess so. But yes, I’ve already accepted the offer to write it. Don’t worry, I’ll vet everything through the UN before publication. The IHA’s secrets are safe with me.’

  ‘I never doubted it,’ Seretse assured her. ‘But on the subject of secrets, you clearly have some of your own. I am being pressured, particularly by the US State Department, to find out exactly what happened on your most recent operation. We know there was a gun battle at the lake in Norway that resulted in several deaths, and that according to Mr Trulli and the other survivors you left the scene with a Russian; but after that you vanished from the radar until reappearing in Moscow, then travelled back to Sweden . . . and finally turned up in northern Canada! All without a word of explanation beyond your decidedly sparse report. And Dr Skilfinger has been equally uncommunicative, except to say that you and Eddie saved her life.’ He leaned forward. ‘What is going on, Nina?’