He spun, raising the rifle—

Eddie reached him first, pulling a trigger of his own – on the Fast Ice drill.

A foot-long steel screw spinning at two thousand revolutions per minute punched into the mercenary’s chest, its clawed tip cutting effortlessly through flesh and bone into the man’s heart. August managed a gargling scream before crumpling.

‘You know the drill,’ Eddie told him. He detached the bloodied rod from the chuck, then collected the dead man’s gun. ‘Cheng! Imka! It’s me, Eddie – are you okay?’

‘Yes, we’re here!’ was Cheng’s fearful reply. ‘What happened to that man?’

‘He’s screwed. Come on, the whole fucking place is coming apart!’

Imka emerged first, Cheng behind her.

‘Where is Professor Wilde?’ he asked, before gulping at the sight of August’s chest wound.

‘On the cliff – I hope.’ He set off, hoping they would have the sense to follow.

They did – as far as the frozen remains. ‘Oh no, no!’ wailed Imka, staring in horror. ‘It’s Arnold!’

Eddie told Cheng to keep going before returning to her. ‘You don’t know that.’

‘No, I do! This boot, it’s a Scarpa, bright orange – I bought it for him! He . . . he was . . .’ She struggled to breathe in her shock.

‘I’m sorry,’ said Eddie, grim-faced, ‘but we have to go. Now!’ As much as he wanted to offer sympathy, time was running out. He pulled her with him after Cheng.

‘Jesus Christ!’ Nina gasped. The swinging anchor had hit the base of Roche’s spine, punching straight through his body to bury itself two feet deep into the icy cliff. The mercenary was still alive, twitching and shuddering – though he wouldn’t be for long as his blood sluiced down the frozen slope. His gun fell from his spasming hand and slid towards the water, followed by one of his legs.

The most immediate threat had been removed, but she was far from out of danger. The anchor’s impact had damaged the ledge, forcing her to dig her crampon spikes into the wall to keep from slipping – and the noise of half a ton of steel slamming into the cavern’s side had drawn the attention of the two other mercenaries.

Harhund was partway around the outcrop, Martel just reaching the end of the crack. The leader shouted an order. Nina couldn’t hear it over the crashing waves, but the gist was obvious: get her! Martel started back towards her.

The ledge broke away from beneath the anchor, taking a few feet either side with it. She yelped and shifted her footing as another lump beneath one boot disintegrated in sympathy. Her only chance of escape was to reach the fortress – but how?

Roche was by now mercifully dead. If she could jump across the gap and grab the anchor pinning him, she might be able to clamber around and reach the ledge on the other side.