And before Erlendur had the chance to do anything she’d pushed him away and run out of the flat, down the stairs and into the street where she vanished into the cold autumn rain.

He closed the door slowly behind her, wondering whether he’d used the right approach. It was as if they could never talk to each other without arguing and shouting, and he was tired of that.

With no appetite for his food any more, he sat back down in his armchair, staring pensively into space and worrying about what Eva Lind might resort to. Eventually he picked up the book he was reading, which lay open on a table beside the chair. It was from one of his favourite series, describing ordeals and fatalities in the wilderness.

He continued reading where he’d left off in the story called “Lives Lost on Mosfellsheidi” and he was soon in a relentless blizzard that froze young men to death.

The rain poured down on Erlendur and Sigurdur Oli as they hurried out of their car, ran up the steps to the apartment block on Stigahlid and rang the bell. They had contemplated waiting until the shower ended, but Erlendur got bored and leapt out of the car. Not wanting to be left behind, Sigurdur Oli followed. They were drenched in an instant. Rain dripped off Sigurdur Oli’s hair and down his back and he glared at Erlendur while they waited for the door to open.

At a meeting that morning the policemen who were engaged on the investigation had considered the possibilities. One theory was that Holberg’s murder was completely without motive and the attacker had been prowling around the quarter for some time, possibly even for days: a burglar looking for somewhere to break in. He had knocked on Holberg’s door to find out if anyone was at home, then panicked when the owner answered it. The message he had left behind was merely intended to lead the police astray. It had no other immediately obvious meaning.

On the same day that Holberg was murdered, the residents of a block of flats on Stigahlid had reported that two elderly women, twin sisters, had been attacked by a young man in a green army jacket. Someone had let him in the front entrance and he had knocked on the door to their flat. When they answered he burst in, slammed the door behind him and demanded money. When they refused he punched one of them in the face with his bare fist and pushed the other to the floor, kicking her before he finally fled.

A voice answered the intercom and Sigurdur Oli said his name. The door buzzed and they went inside. The stairway was badly lit and smelled unhygienic. When they reached the upper floor one of the women was standing in the doorway waiting for them.

“Have you caught him?” she asked.

“Unfortunately not,” Sigurdur Oli said, shaking his head, “but we’d like to talk to you about…”

“Have they caught him?” said a voice inside the flat and an exact replica of the first woman appeared before them in the doorway. They were aged about 70 and both wore black skirts and red sweaters. They were of stout build with grey, bouffant hair atop round faces with an obvious look of expectation.

“Not yet,” Erlendur said.

“He was a poor wretch,” said woman number one, whose name was Fjola. She invited them in.

“Don’t you go taking pity on him,” said woman number two, whose name was Birna, and she closed the door behind them. “He was an ugly brute who hit you over the head. That’s some wretch for you, eh.”

The detectives sat down in the sitting room, looking first at the women in turn and then at each other. It was a small flat. Sigurdur Oli noticed two adjoining bedrooms. From the sitting room he could see into the small kitchen.

“We read your statement,” said Sigurdur Oli, who had flicked through it in the car on the way to the sisters. “Can you give us any more details about the man who attacked you?”

“Man?” Fjola said. “He was more like a boy.”

“Old enough to attack us though,” Birna said. “He was old enough for that. Pushed me to the floor and kicked me.”

“We haven’t got any money,” Fjola said.

“We don’t keep money here,” Birna said. “And we told him so.”

“But he didn’t believe us.”

“And he attacked us.”

“He was wild.”

“And swore. The things he called us.”

“In that horrible green jacket. Like a soldier.”

“And wearing these sort of boots, heavy, black ones laced up his legs.”

“But he didn’t break anything.”

“No, just ran away.”

“Did he take anything?” Erlendur said.

“It was like he wasn’t in his right mind,” said Fjola, who was trying as hard as she could to find some saving grace for her attacker. “He didn’t break anything and he didn’t take anything. Just attacked us when he realised he wouldn’t get any money from us. Poor wretch.”

“Stoned out of his mind more like,” Birna spat out. “Poor wretch?” She turned to her sister. “Sometimes you can be a real dimwit. He was stoned out of his mind. You could tell from his eyes. Harsh, glazed eyes. And he was sweating.”

“Sweating?” Erlendur said.

“It was running down his face. The sweat.”

“That was the rain,” Fjola said.

“No. And he was shaking all over.”

“The rain,” Fjola repeated and Birna gave her the evil eye.

“He hit you over the head, Fjola. That’s the last thing you needed.”

“Does it still hurt where he kicked you?” Fjola asked, and she looked at Erlendur. He could have sworn her eyes were dancing with glee.

It was still early morning when Erlendur and Sigurdur Oli arrived in Nordurmyri. Holberg’s neighbours on the ground and first floor were waiting for them. The police had already taken a statement from the family who had found Holberg but Erlendur wanted to talk to them further. A pilot lived on the top floor. He’d arrived home from Boston at midday on the day Holberg was murdered, gone to bed in the afternoon and not stirred until the police knocked on his door.

They started with the pilot, who answered the door unshaven and wearing a vest and shorts. He was in his thirties, he lived alone and his flat was like a rubbish heap; clothes strewn everywhere, two suitcases open on a newish leather sofa, plastic bags from the duty-free shop on the floor, wine bottles on the tables and open beer cans wherever there was space for them. He looked at the two of them then walked back inside the flat without saying a word and slumped into a chair. They stood in front of him. Couldn’t find anywhere to sit. Erlendur looked around the room and thought to himself that he wouldn’t even board a flight simulator with this man.

For some reason the pilot started talking about the divorce he was going through and wondered whether it could become a police matter. The bitch had started playing around. He was away, flying. Came home from Oslo one day to find his wife with his old school-friend. Godawful, he added, and they didn’t know which he found more godawful, his wife being unfaithful to him or his having to stay in Oslo.

“Concerning the murder that was committed in the basement flat,” Erlendur said, interrupting the pilot’s slurred monologue.

“Have you ever been to Oslo?” the pilot asked.

“No,” Erlendur said. “We’re not going to talk about Oslo.”

The pilot looked first at Erlendur and then at Sigurdur Oli, and finally he seemed to cotton on.

“I didn’t know the man at all,” he said. “I bought this flat four months ago, as far as I understand it had been empty for a long while before that. Met him a few times, just outside. He seemed all right.”

“All right?” Erlendur said.

“Okay to talk to, I mean.”

“What did you talk about?”

“Flying. Mostly. He was interested in flying.”

“What do you mean, interested in flying?”

“The aircraft,” the pilot said, opening a can of beer that he fished from one of the plastic bags. “The cities,” he said, and gulped down some beer. “The hostesses,” he said and belched. “He asked a lot about the hostesses. You know.”