Helsingin Sanomat forecast minus temperatures in double figures and cloudy conditions for Helsinki. ‘Great,’ Eusden muttered to himself, leafing through page after page of impenetrable Finnish headlines. ‘Just great.’ Then he saw the magic word: Mjollnir. And then…

A photograph adjoining an article in the business section of the paper analysing, as far as he could tell, Mjollnir’s performance since its takeover of Saukko Bank, showed two smiling besuited captains of commerce in a wood-panelled conference room. The caption beneath identified them as Arto Falenius and…Tolmar Aksden.

Falenius was a debonair middle-aged figure in pinstripes, with a spotted tie and a matching handkerchief billowing from his breast pocket, greying hair worn daringly long, handsome face tanned enough to suggest he spent a sizeable chunk of the Nordic winter in sunnier climes. His status was unclear to Eusden. Saukko’s CEO, perhaps, celebrating a synergetic merger? The photograph might not be contemporary, of course. It could easily date from the previous autumn.

There was certainly no doubt, however, that Aksden was the dominant partner. He was taller than Falenius by several inches, older by a couple of decades and altogether more serious. His suit and tie were unpatterned, his smile cooler, his gaze harder. There was a bulk about him, of muscle and intellect. He looked a lot like his brother, but without as many visible ravages of self-indulgence. Instead, there was calmness and certainty in his face, confidence edged with something like defiance in his expression. Or was it contempt? Yes. There was a hint of that in his bearing and demeanour: an ingrained knowledge of his own superiority.

A movement at the door suddenly caught Eusden’s eye. He looked up just in time to see Koskinen exiting the café, shrugging on the overcoat he had retrieved from the hatstand as he went. He moved fast, without looking back.

‘Osmo!’ Eusden called. But he was too late. The door had already closed. He stood up, baffled and dismayed. What was the fellow playing at? He headed after him.

But the waiter intercepted, clutching the bill. There was a flurry of confusion and misunderstanding. Eusden wasted precious minutes offering Danish, then Swedish, kroner in payment before pulling out some euros. By the time he reached the street, Koskinen had vanished. He swore, loudly enough to offend a woman walking by, and asked himself again what Koskinen’s game could possibly be. His behaviour was inexplicable.

Then Eusden remembered him looking out of the window just before excusing himself. What had he been looking at? The cathedral was the obvious answer. It dominated the view across the square. Had someone on the steps leading up to it signalled to him? Had the time shown on its clock triggered his move?

In one sense, it did not matter. The fact was that he had gone. Eusden shivered, realizing as the chill bit into him that he had left his coat in the café. He turned back.

A man was standing directly in his path dressed in a black cap and dark casual clothes. He was tall and muscular and stony-faced. For a second, Eusden gaped at him. And the man stared expressionlessly back. Eusden heard a vehicle pull up at the kerb next to him, skidding in the ice-clogged gutter. Then the man kneed him in the groin with such force that he doubled up, his eyes misting with pain. He was seized about the shoulders. A heavy hand descended on to his neck. He was pushed and pulled backwards, his heels dragging on the pavement.

Suddenly, he was on the floor of a Transit van, the door sliding shut as it accelerated away. There were two men above and around him, lurching with the motion of the van. He heard the sound of tape being peeled from a roll. He tried to sit up, but was shoved back down. His hands were yanked round behind him. The tape was wound tightly round them and his ankles simultaneously. Within seconds, he was trussed and helpless.

‘For God’s sake,’ he gasped. ‘What do you-’ Then a strip of tape was slapped over his mouth as well.

‘Change of plan, Mr Eusden.’ Eusden twisted in the direction the voice had come from and saw Erik Lund smiling at him through the grille from the passenger seat. ‘For you.’ He felt something sharp jab into his left arm. ‘My advice is to stop struggling.’

Eusden had no intention of taking Lund’s advice. But within seconds he had no choice in the matter. The jolting of the van merged with waves of wooziness that swept into his brain. The figures around him blurred into monochrome – then merged into blackness.

THIRTY-SEVEN

For a second, when he woke, Eusden believed he was in bed at home in London, the pounding in his head and the stiffness in his limbs attributable to a serious hangover. But no. Reality pounced on his thoughts with the force of a nightmare. He was still in the van, alone now, alone and cold and enveloped in darkness.

A trace of light was seeping in from somewhere, however, enough to cast shadows within the van. He crawled on to his knees and looked about him as best he could. A shutter was rattling somewhere outside the vehicle, but no other sound reached him. How long he had been wherever he was he had no way of knowing. His wristwatch was out of sight. Why he had been left there was equally impenetrable. ‘Change of plan for you,’ Lund had said, as if this had always been the plan as far as Mjollnir were concerned. Koskinen’s behaviour confirmed as much. A trap had been laid for him. But why?

He had to break free. For the moment, that was all he could think of. A conjunction of shadows towards the front of the van revealed a tear of some kind in one corner of the grille sealing off the cab. He worked his way over for a closer look. The frame was dented and several wires had sprung out of their sockets. The loose ends were stiff and sharp. He turned round, stretched his arms up behind him and felt one of the wires against the heel of his hand. He manoeuvred so that it snagged on the tape, then sawed away until the tape split.

Within a couple of minutes, he had released his hands. He teased the strip off his mouth, sat down and peered at his watch. It was a few minutes past two. Koskinen should be in the process of collecting the caseload of bearer bonds around now. He must already have given Pernille some cooked-up explanation of Eusden’s disappearance. He felt in his pocket for his phone. But they had taken it. No surprise, really. He unwound the strips binding his ankles and prised at the handle of the side door. Locked. That was no surprise either. He stood up and moved to the rear doors. Also locked. There was no way out. He thumped pointlessly at the nearest door panel, then lowered himself to the floor, flexing fruitlessly at the handle as he sat there, staring glumly into the shadows. God, it was cold. Did Lund mean him to freeze to death?

As much to warm himself as with any realistic hope of getting out that way, he went back to the dented grille and tried to pull it further loose. No more wires budged. Apart from a gash to his finger, he achieved nothing. He slumped down on the floor, sucking the wound, cursing Lund and Birgitte Grøn – and Marty for dragging him into all this.

Unmeasured minutes passed while he contemplated the horrifying nature of his plight. The invisible shutter went on rattling. The cold began to gnaw at him. He started to shiver. ‘Fucking hell, Marty,’ he said aloud, ‘how could you-’

A sound deeper and farther away than the rattling shutter reached his ears. It was a car engine. It stopped and was succeeded by a burble of human voices. There was the creak of a door opening. The light strengthened marginally. Through the grille and the windscreen beyond, he could see shadows moving on a brick wall. A switch was flicked and a fluorescent lamp pulsed into life overhead. A key turned in the rear door of the van. One of them swung open. Then the other.