‘I do. Otherwise I wouldn’t have let you go down to the bottom of the world, would I?’

He chuckled. ‘You want to swap places? You’re the one who knows all about ships . . .’

‘I’m fine here, thanks. Did I mention it’s twenty-two Celsius today?’

‘No, and I wish you hadn’t. But the Dionysius isn’t equipped for salvage work, so we’d have to—’

He stopped at a sudden rasp from the radio. Havman snatched it up. ‘Hello, hello!’ he said. ‘Are you all right?’

An ear-shredding screech of static – then a voice pierced the distortion. ‘Het heeft haar gedood! Het heeft haar gedood! Mijn God, help me!’

‘It’s Wim!’ said Bekker, jumping up in alarm. His native Afrikaans was very similar to Dutch, and he knew exactly what Stapper was saying: It killed her! It killed her! My God, help me! ‘Wim, what happened? What killed her – what happened to Sanna?’

The crew reacted in shock.

‘Help me! Help!’ came the panicked reply. ‘Oh God, it’s coming after me!’

‘What is?’

‘De demon! Sanna woke it up! It—’

Stapper’s words were cut off, not by static but a loud thump, followed by banging sounds. He had slipped, skidding down an icy slope – then came a pained shout as he hit something. But it was not the only shout. In the background was another voice, with a strange, throaty echo to it that barely sounded human.

Then the channel fell silent.

‘Wim!’ yelled Bekker. ‘Wim, can you hear me? Wim!’ He turned to Havman. ‘We’ve got to help him! We need to get into the cave. If you launch the lifeboat—’

‘Are you mad?’ said the Swede. ‘There’s a murderer running around!’ He hesitated, then with clear trepidation issued orders to the crew. ‘We’ll take the whole ship inside,’ he told Bekker. ‘We’ll be protected while we look for him.’

The Dionysius’s engines came to life. Bekker stared fearfully at the shadowy cave mouth, then belatedly realised that someone was calling his name. ‘Arnold! Arnold, what’s going on?’ said Imka over the satellite link.

‘Imka, something’s happened,’ he replied. ‘Wim and Sanna are in trouble.’

‘What kind of trouble? What—’

‘I’m sorry, I have to go. I’ll call you back as soon as we’ve found them. I love you.’

‘I love you too. But—’

He ended the call and rushed to the windows. The ship quickly closed on the iceberg. Dull thunks echoed through the hull as the prow struck bobbing growlers. The entrance loomed ahead. ‘Will we fit?’

‘We’ll fit,’ said Havman grimly. ‘Try to get him on the radio.’

Bekker called Stapper, to no avail. The captain slowed, bringing the Dionysius into line with the cave’s tall but relatively narrow mouth. The South African watched – then suddenly remembered something. ‘He said “it” . . .’

Havman didn’t divert his gaze from the icy passage. ‘What?’