‘Anyway, among these scientist refugees was a guy by name of Hilbert Lake, who had led a research team involved in some kind of really cutting-edge physics research. He and his team all upped and came to Iceland when they got the invite, except they ended up getting killed during the invasion.’

‘Ernest Schultner never told me any of this during my last briefing,’ I said.

‘That’s because I’m not supposed to know any of this.’

‘So how . . . ?’

‘Well,’ she said in a faux-conspiratorial whisper, ‘I heard something from Winnie, who heard it from a guy called Wallace.’

‘Winnie? You mean Winifred Quaker?’ Winifred was one of the Pathfinders I had met, although I was still to meet a few who were off on various long-term missions. They had been absent from the island base since before my arrival.

Nadia nodded, and it occurred to me that the headlights were now doing a better job of illuminating the cavern than they had just moments before. ‘Wallace is another Pathfinder. It seems he was in the base compound back on Easter Island, helping them sort out some computer network problem. He overheard your man Ernest Schultner talking to Kip Mayer . . .’

‘And Mayer is . . . ?’

‘Second-in-Command to Mort Bramnik. Bramnik’s the man in charge of the whole Easter Island Forward Base.’ Another I hadn’t yet encountered. ‘Anyway,’ she continued, ‘from what Wallace overheard, it sounded like Lake and his team had been working on a prototype transfer stage.’

‘You mean they were building something they could use to escape to a parallel universe?’

‘Yep.’

I frowned. ‘That’s incredible,’ I said. ‘But the Authority already have transfer stages. They can already travel to parallel realities. Why would they need someone else’s research?’

She shrugged. ‘Just do me a favour and don’t ask Schultner, or we’re all in big trouble.’

‘But—’

‘Just remember what Yuichi and I explained back at the start – play your part, don’t complain too much, and especially don’t ask too many questions and one day we all get to retire to somewhere nice and safe.’ She frowned. ‘Is it just me, or is it getting brighter in here?’

After taking me on their grand tour of the multiverse, Nadia and Yuichi had ushered me into the Hotel du Mauna Loa, back on Easter Island – the place from which Yuichi had shot me with a tranquillizer dart a second time as I tried to evade capture. Here, they explained to me what retirement was.