Outside in the yard it was practically dark now, but Luke snapped off the torch on his phone and blinked several times. He had good night vision, better than most people’s: it would just take a few seconds to come back. Moments later, he was across the yard and in through the back door to the house; it was unlocked.

‘Kristian?’ he called.

No answer.

Luke could see he was in the kitchen, there were pots hanging on the wall, their shiny surfaces reflecting the last vestiges of ambient light from the dying day outside. He froze mid-step. Someone was upstairs, right above him. Someone heavy. He could tell from the tread that it was not Kristian. Luke’s entire body went into alert state, wiring itself for danger.

Moving softly now, on the balls of his toes, he went over to the row of utensils above the cooker, searching for a suitable weapon until he found it. A bread knife. Not ideal, he would have preferred something a lot sharper, but its serrated teeth could still do some damage and it would have to do. If his unseen quarry upstairs was armed, Luke would have to be either very quick or very inventive with it, preferably both.

He considered his options. None were good. He could phone for police back-up, but that could take hours and, anyway, he wouldn’t know how to begin to direct them to this place. He could sit it out here in the kitchen, waiting for his opponent to come down the stairs, then rush him. But what if he didn’t come down? And what if he did, and the guy just simply flipped a light switch, saw Luke and shot him? Chances were, whoever was in this house would know their way around it a damn sight better than Luke did. But there was another, more pressing argument propelling him to act now. Kristian could well be lying up there, unconscious or bleeding to death.

One wooden step at a time, Luke made his way up the stairs, painstakingly slowly, dreading each creak that never quite came. Everything about this situation was wrong: he was alone, with no back-up, unarmed and facing an invisible enemy in a darkened house that he would know and Luke didn’t. At the top of the stairs he stopped and listened, the bread knife tensed in his hand. From outside came the mournful lament of the wind – and was there something else? It sounded almost like heavy breathing …

His eyes were still adjusting to the almost total darkness when suddenly there was a crash and something flew into his face. Luke reacted instinctively, trying to sweep it away with his free arm and dropping into a fighting crouch. But it was just a curtain, flapping wildly in the wind. Someone had opened a window and now the draught was coursing through the entire darkened house.