The MS Horisont nosed out of Þorlákshöfn harbour into a grey swell. Wada watched the harbour wall fall away behind the ship through the porthole of her cabin, calculating it would soon be acceptable for her to show herself on the small portion of the deck she’d been given access to.

The skipper, a taciturn, grizzle-bearded man called Jakobsen, had made it clear Wada was aboard on sufferance. She had no doubt he’d been paid well to transport her, but that evidently didn’t extend to treating her courteously. As soon as Espersen had gone back ashore, he told her bluntly that going on deck when the ship was in harbour, visiting the bridge without his permission or attempting to engage with the crew at any time would result in her being locked in her cabin. After her experiences at Stóri-Asgarbær, this wasn’t something she wanted to risk, so she intended to follow his orders to the letter.

That was easier in principle than practice, however. She’d woken feeling sick, which she attributed to diesel fumes tainting the atmosphere in her cabin. She longed for some lungfuls of fresh air. But another cause of sickness – the rolling of the vessel – was already making itself felt. It promised to be a long three days to Rotterdam.

Eventually, though, the tedium and discomfort of the voyage would give way to the unpredictability of her next exploration of the secrets of Emergence. She had those secrets in her hand, on the memory stick Espersen had given her, but without a computer the stick was just a useless piece of plastic.

That would change once she was ashore. But for now all she could do was wait. Another look through the porthole showed the harbour wall as just a dark line on the horizon. Iceland was behind them.

With the memory stick wedged securely in her pocket, she headed for the door.

Nick found it hard to tell whether Kate was disappointed by his failure to meet his father in Iceland or not. She sympathized with him genuinely enough, but he nonetheless detected an unspoken relief that Peter Driscoll, man of mystery, hadn’t entered their lives after all. She seemed to doubt whether Nick would ever in fact hear from him. Or was it that she hoped he never would?

Either way, a resumption of normality was clearly what suited her best. And Nick tried hard to behave as if it suited him too.The situation was out of his control anyway. Driscoll knew where he was. The next move was up to him.

On Good Friday, Nick called round at April’s house, early enough to be confident of finding her in. He had to tell her something about what had happened.