Harry knew he was dead when he heard footsteps on the stairs. On their way down. They came slowly, hesitantly. Then faster. Then they raced down. Harry saw a figure dive out of the mist. A reeling ghost in a white shirt and black suit. He hit the banister, bent in the middle and slid lifeless down to the newel post. Harry saw the frayed edges of the wounds in the back of the suit where the bullets had entered. He walked over to the body, grabbed the fringe and lifted the head. Felt sensations of asphyxiation and had to fight the impulse to pull off the gas mask.

One bullet had torn half of the nose away as it exited. Nonetheless, Harry still recognised him. The little guy from the doorway at Hotel Leon. The man who had shot at him from the car in Madserud alle.

Harry listened. There was silence except for the hiss of the tear-gas cartridges from which white smoke was still gushing forth. He retreated to the living-room window, found the rucksack, inserted a fresh magazine and stuffed one under his bullet-proof vest. Only now did he notice the sweat running down the inside.

Where was the big man? And where was Dubai? Harry listened again. The hiss of the gas. But hadn’t he heard footsteps on the floor above?

Through the gas he glimpsed another room and an open door leading to the kitchen. Only one closed door. He stood beside the door, opened it and pointed the riot gun inside and fired twice. Closed the door and waited. Counted to ten. Opened and entered.

Empty. Through the smoke he identified bookshelves, a black leather armchair and a large fireplace. Above it hung a painting of a man wearing a Gestapo uniform. Was this an old Nazi house? Harry knew the Norwegian Storm Trooper boss Karl Marthinsen had been living in a confiscated house in Blindernveien when he ended his days riddled with bullets outside the Science Building.

Harry retraced his steps, went through the kitchen, through the door behind, to the typical maid’s room of the time, and found what he was looking for, the back staircase.

Usually these stairs had also functioned as a fire escape, but these ones didn’t stop at an external door, quite the opposite, they continued down to a cellar, and what had once been a back door had been bricked up.

Harry checked that there was still a gas cartridge left in the magazine and mounted the stairs in long, soundless strides. Fired the last cartridge into the corridor, counted to ten and followed. Pushed open the doors, with stabbing pains in his neck, but still managed to concentrate. Apart from the first door, which was locked, all the rooms were empty. Two of the bedrooms looked to be in use. The bed in one didn’t have any sheets on though, and Harry could see the mattress was dark, as if drenched in blood. On the bedside table in the second bedroom there was a Bible. Harry studied it. Cyrillic letters. Russian Orthodox. Beside it a prepared zjuk. A red brick with six nails in. Exactly the same thickness as the Bible.

Harry walked back to the locked door. The sweat inside the mask had made the glass mist up. He leaned back against the opposite wall, lifted his foot and kicked at the lock. The door cracked at the fourth kick. Harry crouched down and fired a salvo into the room, heard the tinkle of glass. Waited until the smoke from the corridor had drifted inside. Went in. Found the light switch.

The room was bigger than the others. The four-poster bed by the long wall was unmade. A blue jewel on a ring flashed from the bedside table.

Harry put his arm under the duvet. Still warm.

He looked around. Whoever had just been lying in this bed might of course have left the room and locked it after him. Had the key not still been on the inside. Harry checked the window: closed and locked. He examined the solid wardrobe on the short wall. Opened it.

At first glance it was a standard wardrobe. He pressed the back wall. It opened.

An escape passage. German thoroughness.

Harry shoved the shirts and jackets to the side and poked his head through the false panel. A cold gust of air met him. A shaft. Harry groped. Iron rungs had been hammered into the wall. Looked as if there were more rungs further down; they had to lead to the cellar. An image fluttered through his brain, a detached fragment of a dream. He repressed the image, removed his gas mask and forced his way through the false wall. His feet found the rungs, and when he carefully made his way down and his face was level with the wardrobe floor, he saw something lying there. It was U-shaped, stiffened cotton material. Harry put it in his coat pocket and continued down into the darkness. He counted the rungs. After twenty-two one foot touched terra firma. But as he was about to lower the other foot, the no longer quite so firma terra moved. He lost his balance, but his landing was soft.

Suspiciously soft.

Harry lay still and listened. Then he took the lighter from his trouser pocket. Flicked it, let it burn for two seconds. Let it go out. He had seen what he needed.

He was lying on top of a man.

An unusually large and unusually naked man. With skin as cold as marble and the typical blue pallor of recent corpses.

Harry detached himself from the body and stepped across the concrete floor to a bunker door he had noticed. With his lighter lit he was a target; with more light everyone was a target. He held the MP5 at the ready while flicking the switch with his left hand.

A line of bulbs came on. They stretched along a low, narrow tunnel.

Harry established that he and the naked man were alone. He looked down at the body. It lay on a rug on the ground and had a bloodstained bandage round its stomach. From the chest a tattoo of the Virgin Mary stared up at him. Which, as Harry knew, symbolised that the bearer had been a criminal since his childhood years. As there were no other visible signs of injury Harry assumed it was the wound under the bandage that had killed him, in all probability caused by a bullet from Truls Berntsen’s Steyr.

Harry pressed his fingers against the bunker door. Locked. The tunnel ended at a metal plate cut into the wall. Rudolf Asayev had had, in other words, only one way out. The tunnel. And Harry knew why he tried all the other exits first. The dream.

He stared down the narrow tunnel.

Claustrophobia is counterproductive, it gives false signals of danger, it is something that has to be fought. He checked that the magazine was slotted into his MP5 properly. Sod it. Ghosts exist only if you let them exist.

Then he set off walking.

The tunnel was even narrower than he had imagined. He ducked, but he still banged his head and shoulders on the moss-covered ceiling and walls. He tried to keep his brain active so as not to give claustrophobia room to grow. And thought this must have been an escape passage the Germans had used; it all fitted with the bricked-up back door. Force of habit ensured he kept his bearings, and unless he was mistaken he was heading for the neighbouring house with an identical water tower. The tunnel had been built with meticulous care; there were even a number of drains in the floor. Strange that the Autobahn-constructing Germans should have built such a narrow tunnel. As he formulated the word ‘narrow’, claustrophobia took a stranglehold on him. He concentrated on counting his paces, tried to visualise where he could be in relation to what was beyond the hill. Beyond the hill, outside, free, breathing air. Count, count for Christ’s sake. When he reached 110 he saw a white line on the ground beneath him. He could see the lights stopped some way ahead and when he turned he realised the line had to be marking the middle of the tunnel. From the small steps he had been forced to take he estimated the distance he had walked to be between sixty and seventy metres. Soon there. He attempted to quicken his pace, shuffling his feet beneath him like an old man. Heard a click and looked down. It came from one of the drains. The bars moved until they overlapped, like air vents in a car. And at that moment he heard a different noise, a deep rumble behind him. He turned.