‘Hope you’re right,’ said Nina as they approached. But to her relief, the cops gave them no more attention than any other passers-by. ‘Okay,’ she said to Krämer after they passed, ‘what do you want to do with the key? As long as you’ve got it, those guys might keep coming after you. And don’t use the word “fifty”, or anything close to it,’ she chided. ‘Cheng, if you pay him that much, I’ll give you an F for the semester right here and now!’

The German made an aggrieved noise. ‘You have to give me something. I cannot go back to my room in case they are waiting for me!’

Cheng thought for a moment. ‘What about . . . twenty-five thou—’

‘Done,’ Krämer snapped.

Cheng blinked.

Nina frowned, but the Chinese youth was already opening his bag. ‘Jeez, at least keep it hidden,’ she said. ‘And get out of the cops’ sight before you start handing out wads of banknotes. You’ll get us arrested, or mugged, or both.’

‘Down here,’ said Eddie, rounding a corner and finding a darkened doorway. He stood guard, Nina partly watching the street and partly glaring in annoyance as Cheng handed the German half his money.

‘Okay, now give him the key,’ she said pointedly after Krämer tucked the notes away. He gave her a dirty look, but passed the artefact to Cheng. ‘Right, you’ve got it – so put it away before anyone sees it.’ Her student dropped it into the holdall and closed the zipper. She looked back at the sailor. ‘Anything else you can tell us about the key or what Stapper said?’

Krämer shook his head. ‘Not much. There was a big iceberg near where we found him, but that is all I can think of. Stapper’s ship wasn’t wrecked on it, though. We searched. The iceberg could have rolled over and crushed it into the water.’

‘Okay. I guess we’re done, then.’

‘Thank you,’ said Cheng as Krämer quickly departed.

‘Don’t thank him,’ Eddie said. ‘That thing might still land you in trouble.’

‘We have to get out of Hamburg,’ said Nina. ‘Maybe those guys chasing us were arrested in the fight, but I don’t want to bet my life on it.’

Eddie nodded. ‘We should go to a different subway station. There’s one at St Pauli.’ He jabbed a thumb eastwards.

‘Good idea.’ They set off.

‘So, we’ve got this thing. Where are we going? Home?’

‘No,’ said Nina. ‘Well, not directly. There’s someone we need to talk to first – Wim Stapper.’

‘What, the guy from the ice? Why?’

She glanced at Cheng’s bag. ‘He found a Veteres artefact, somewhere off Antarctica. He’s the only person who can tell us anything more about where it came from – and what he meant by “demons”.’