A quick cross-change at Longyearbyen airport and Luke was on a flight to London via Tromsø and Oslo. Transiting through Tromsø, the same team of medics who had vaccinated him on the way out had screened him, checked him for fever and cleared him of any contamination. He had given his contact report to the NIS intelligence officer in the lounge and agreed to file a full account from London. And now here he was, back in the Battersea flat that he and Elise shared on the south bank of the Thames; he had even managed to grab a few hours’ sleep on the way south.

But now he saw he had three missed calls, all from the office. He looked down at Elise, still asleep, her head buried beneath a pillow and her back turned away from him. Luke picked up the phone from the bedside table and took it into the next room, closing the door behind him and pressing ‘call back’. A crisp, no-nonsense voice answered immediately. Angela Scott at SIS headquarters, in Vauxhall Cross, contacting him at this barely respectable hour. He shook his head. Did she ever rest? Apparently not. But over the three years he had known her, Luke had acquired a lot of respect for Angela. Her calm, measured approach had steered them through more than one crisis. And beyond that, she had stuck up for him when others in that building had wanted his scalp, branding him ‘a maverick’, ‘a loose cannon’ and, as someone had put it, ‘a bloody cowboy’. Truth be told, he probably wouldn’t still be working for the Service now if it weren’t for her.

‘Great. You’re up,’ she said. ‘I was afraid you’d still be asleep. Good flight, I hope?’ She didn’t wait for him to answer. ‘Look, I won’t sugar-coat this, Luke. You’re about to get a knock on the door, so please don’t be alarmed. We got you out of Svalbard in such a rush they didn’t have time to give you a full-spec medical screening.’

‘Yes, they did. In Tromsø. I got the all-clear.’

‘Oh.’ She sounded deflated. ‘Well, apparently that was a bit cursory and now the Porton Down people need to give you the once-over. You have just been in close proximity to a lethal pathogen. Look, I’m sorry, Luke, I know this is probably the last thing you feel like doing right now, but we’re still getting to grips with this thing and we can’t exactly have you being the super-spreader, so just bear with us, okay?’

‘All right, so when can we expect this visit?’ he asked.

It was then that the doorbell rang.