ALONE, IN THE dim interior of a traditional wooden house, halfway between mainland Norway and the North Pole, Luke’s breath frosted in the sub-zero air. Beside him, the rapidly cooling corpse of Kristian Berge, a grade-six officer in the Norwegian Intelligence Service, lay exactly as he’d found it. Luke had been careful not to move it, or to touch the black plastic haft of the screwdriver that had ended the man’s life, just in case there were any prints for the forensics people. He wasn’t fazed by being in a room with a dead body. He’d seen plenty from his time on operations in the badlands of Iraq’s Anbar province, in the labyrinthine, mud-walled compounds of Kandahar, and in the parts of West Africa he could never talk about. Some of those people he’d never known, some he’d dispatched himself in the heat of battle, and some had been his mates. But that was in war, in combat, and this was supposed to be peacetime. Somehow, Kristian’s death felt so much more shocking.

Yet Luke was not going to let himself dwell on it. The inquest, the questions, and maybe the accusations would come later. Right now he needed to focus on the tactical, on his own immediate situation. What if Kristian’s killer was not the only human threat inside this sinister building? What if someone else was lurking in the darkness, waiting to catch him off-guard? He looked down at the bread knife still clutched in his hand. It wasn’t much of a defence, but it was all he had. Slowly, quietly, room by room, Luke checked the house, bracing himself for violence each time he opened a door or turned a corner, then breathing out slowly. The building was empty.

He sat down in the kitchen, took a deep breath and called it in to Vauxhall. Checking his watch as he was put through, he realized it was less than seven hours since Angela Scott had expressed her intense displeasure on hearing that Victor Skeet had been shot dead in Barentsburg. Now he had another death to report and this time it was someone on the home team. But their conversation, when he got through, was all business. He told her immediately about Kristian and that his killer was now on the loose somewhere on this frozen archipelago. He told her about the makeshift lab he’d found in the outhouse, the polythene covers, the suspicious-looking containers of fluid and the documents he’d snatched up from beneath the desk in the other room.

‘Send them over,’ Angela said. ‘Send us the photos on your phone now and we’ll get on to them straight away.’ There was a brittleness to her voice, a tension he always noted when an operation was under way. He could hear her clearing her throat. ‘Now,’ she said, ‘about Kristian Berge …’