It was mid-afternoon when they left the restaurant. George argued they really should see Gullfoss now they were so close and there’d still be time to take in Wada’s detour on the way back to Reykjavík. Wada didn’t have much choice but to agree.

According to George’s bellowed enthusings, the falls were an awesome sight, but she had to pull the hood on her borrowed anorak so low to keep out the wind-driven snow that she couldn’t really tell where the spray ended and the snow-bearing clouds began. Warming up over hot chocolate in the visitor centre would have been welcome in other circumstances, but she only wanted to get to Stóri-Asgarbær and eventually George registered her impatience.

‘It’s OK, Umiko. It’s your business opportunity in the boondocks next, I promise. Don’t worry. There’s hours of daylight left.’

And so, with Wada navigating now, they set off.

The version of events Nick had supplied to Kate had him meeting Martin Caldwell that evening. Inventing a message from Martin saying his arrival in Reykjavík had been delayed by twenty-four hours got him off that hook and he planned to report Martin had been further delayed later.

The real question remained, though: was Caldwell in Iceland? Was this where he’d fled after leaving Exeter? Nick got hold of a list of hotels and guesthouses in Reykjavík from the tourist office and started phoning round, asking if Martin Caldwell was staying with them. No was the consistent answer, until … the Hotel Arnarson. Caldwell wasn’t a guest of theirs. But he had been. Until the previous Monday.

‘Are you a relative of Mr Caldwell, or a friend?’

‘A friend. My name’s Miller. Nick Miller. I can’t seem to contact Martin and I’m becoming concerned for his safety.’

‘We have had several enquiries about Mr Caldwell. Actually, the police have been looking for him.’

‘The police? Why?’

‘They did not tell us, sir. But it seems Mr Caldwell has not left Iceland, so …’

‘Who are these other people who’ve been asking after him?’

‘Well …’

‘I’m really very worried. It would be a great help if you could at least put me in touch with some of them.’

There was a pause. ‘To be frank, sir, only two of those who’ve enquired about Mr Caldwell have left names and phone numbers.’

‘Could you give me them?’

‘Mmm. I will have to check with a colleague.’

‘Look, you’re not far from where I am now, so I’ll come and see you and hope your colleague’s given you permission in the meantime. How does that sound?’

‘As you wish, sir.’