Harry nodded.

An hour later they had passed the border and were driving into Goma. On the roadside an emaciated man in a torn jacket was sitting and staring ahead through desperate, crazed eyes. Joe steered the vehicle carefully between the craters in the muddy path. A military jeep was in front of them. The swaying soldier manning the machine gun looked at them with cold, weary eyes. Above them roared aeroplane engines.

‘UN,’ Joe said. ‘More guns and grenades. Nkunda come closer to the city. Very strong. Many people escape now. Refugees. Maybe Monsieur Van Boorst, too, eh? I not see him long time.’

‘You know him?’

‘Everybody know Mr Van. But he has Ba-Maguje in him.’

‘Ba-what?’

‘Un mauvais esprit. A demon. He makes you thirsty for alcohol. And take away your emotions.’

The air-conditioning unit was blowing cold air. The sweat was running down between Harry’s shoulder blades.

They had stopped midway between two rows of shacks, in what Harry realised was a kind of city centre in Goma. People hastened to and fro on the almost impassable path between the shops. Black boulders were piled up alongside the houses and served as foundations. The ground looked like stiffened black icing and grey dust whirled up in the air that stank of rotten fish.

‘La,’ Joe said, pointing to the door of the only brick house in the row. ‘I wait in the car.’

Harry noticed a couple of men stop in the street as he exited the car. They gave him the neutral, dangerous gaze that relayed no warning. Men who knew that acts of aggression were more effective without a warning. Harry headed straight for the door without looking either side, showed that he knew what he was doing there, where he should go. He knocked. Once. Twice. Three times. Bollocks! Bloody long way to come just to The door opened a fraction.

A wrinkled white face with questioning eyes stared at him.

‘Eddie Van Boorst?’ Harry asked.

‘Il est mort,’ said the man in a voice so hoarse it sounded like a death rattle.

Harry remembered enough school French to understand that the man was claiming Van Boorst was dead. He tried in English. ‘My name is Harry Hole. I was given Van Boorst’s name by Herman Kluit in Hong Kong. I’m interested in a Leopold’s apple.’

The man blinked twice. Stuck his head out of the door and looked left and right. Then he opened the door a little more. ‘Entrez,’ he said, motioning Harry in.

Harry ducked beneath the low door frame and just managed to bend his knees in time; the floor inside was twenty centimetres lower.

There was a smell of incense. As well as something else, familiar – the sweet stench of an old man who had been drinking for several days.

Harry’s eyes became used to the dark, and he discovered that the small, frail old man was wearing an elegant, burgundy silk dressing gown.

‘Scandinavian accent,’ said Van Boorst in Hercule Poirot English and placed a cigarette in a yellowing holder between his thin lips. ‘Let me guess. Definitely not Danish. Could be Swedish. But I think Norwegian. Yes?’

A cockroach showed its antennae through a crack in the wall behind him.

‘Mm. An expert on accents?’

‘A mere pastime,’ said Van Boorst, flattered, pleased. ‘For small nations like Belgium you have to learn to look outwards, not inwards. And how is Herman?’

‘Fine,’ Harry said, turning to his right and seeing two pairs of bored eyes looking at him. One from a photo above the bed in the corner. A framed portrait of a person with a long grey beard, powerful nose, short hair, epaulettes, chain and sword. King Leopold, unless Harry was much mistaken. The other pair of eyes belonged to the woman lying on her side in the bed with only a blanket draped over her hips. The light from the window above her fell on her small, supple young girl’s breasts. She responded to Harry’s nod with a fleeting smile that revealed a large gold tooth among all the white ones. She couldn’t have been more than twenty. On the wall behind the slim waist Harry glimpsed a bolt hammered into the cracked plaster. From the bolt dangled a pair of pink handcuffs.

‘My wife,’ said the little Belgian. ‘Well, one of them.’

‘Mistress Van Boorst?’

‘Something of that kind. You want to buy? You have money?’

‘First I want to see what you’ve got,’ Harry said.

Eddie Van Boorst went to the door, opened it a crack and peered outside. Shut it and locked up. ‘Only got your driver with you?’

‘Yes.’

Van Boorst puffed on his cigarette while studying Harry through the folds of skin that gathered when he squinted.

Then he went to a corner of the room, kicked away the carpet, bent down and pulled at an iron ring. A trapdoor opened. The Belgian waved Harry down into the cellar first. Harry assumed it was a precaution based on experience, and did as he was told. A ladder led into pitch darkness. Harry reached solid ground after only the seventh rung. Then a light was switched on.

Harry looked around the room; the ceiling was full height and there was a level cement floor. Shelves and cupboards covered three of the walls. On the shelves were the day-to-day products: well-used Glock pistols, his Smith amp; Wesson. 38, boxes of ammunition, a Kalashnikov. Harry had never held the famous Russian automatic rifle known officially as the AK-47. He stroked the wooden stock.

‘An original from the first year of production, 1947,’ Van Boorst said.

‘Seems like everyone down here has got one,’ Harry said. ‘The most popular cause of death in Africa, I’ve heard.’

Van Boorst nodded. ‘For two simple reasons. Firstly when the Communist countries started exporting the Kalashnikov here after the Cold War, the gun cost as much as a fat chicken in peacetime. And no more than a hundred dollars in wartime. Secondly, it works, no matter what you do with it, and that’s important in Africa. In Mozambique they like their Kalashnikovs so much it’s on their national flag.’

Harry’s eyes stopped at the letters discreetly stamped on a black case.

‘Is that what I think it is?’ Harry asked.

‘Marklin,’ said Van Boorst. ‘A rare rifle. It was manufactured in very limited numbers as it was a fiasco. Much too heavy and large a calibre. Used to hunt elephants.’

‘And humans,’ Harry said softly.

‘Do you know the weapon?’

‘World’s best telescopic sights. Not exactly something you need to hit an elephant at a hundred metres. Perfect for an assassination.’ Harry ran his fingers along the case as the memories streamed back. ‘Yes, I know it.’

‘You can have it cheap. Thirty thousand euros.’

‘I’m not after a rifle this time.’ Harry turned to the shelving unit in the middle of the room. Grotesque white wooden masks grimaced at him from the shelves.

‘The Mai Mai tribe’s spiritual masks,’ said Van Boorst. ‘They think that if they dip themselves in holy water, the enemy’s bullets cannot hurt them. Because the bullets will also turn to H2O. The Mai Mai guerrillas went to war against the government army with bows and arrows, shower hats on their heads and bath plugs as amulets. I am not kidding you, monsieur. Naturally, they were mown down. But they like water, the Mai Mai do. And white masks. And their enemies’ hearts and kidneys. Lightly grilled with mashed corn.’

‘Mm,’ Harry said. ‘I hadn’t expected that such a basic house would have such a full cellar.’

Van Boorst chuckled. ‘Cellar? This is the ground floor. Or was. Before the eruption three years ago.’

Everything fell into place for Harry. Black boulders, black icing. The floor upstairs that was lower than the street.

‘Lava,’ Harry said.

Van Boorst nodded. ‘It flowed straight through the centre and took my house by Lake Kivu. All the wooden houses around here burned to the ground; this brick house was the only one left standing, but was half buried in lava.’ He pointed to the wall. ‘There you can see the front door to what was street level three years ago. I bought the house and just put in a new door where you entered.’