There was no question in the world he would rather answer, because his old car was, of course, apple-green. Green. Freedom.

‘My parents bought it.’

‘Write about the car on this piece of paper. How much did they pay for it?’

‘Thirty-five thousand kroner, about five thousand euros,’ said Daniel.

‘You stupid boy. Did you really sell your car to your own family?’

He wrote it all down: that he had bought it new in 2007 for 110,000 kroner; that it was a Chevrolet Matiz with a 0.8 litre engine; that a medal from the Danish national championships hung from the rear-view mirror; and that the car was apple-green.

‘OK,’ said George. ‘Daniel, you are going home.’

They hadn’t said it so directly when any of the other hostages had been freed and the relief that Daniel felt for a moment was replaced by anxiety. What if they knew the code with green, red and amber? What if they had tortured Pierre and he had told them everything?

The Beatles disappeared and Daniel turned to the others, who knew the code with the apple-green car. Fear showed on their faces. They couldn’t hide the fact that they had only one hope: that they would soon be released too.

Yet they all gave Daniel a hug.

‘You’ve earned it,’ one said, but Daniel couldn’t take it in. The idea that he might be the last man to leave the prison alive was unbearable.

‘If you have something I should say once I’m out, tell me,’ he urged.

James stood up and gave Daniel a warm embrace and then he sat on his blanket between his countrymen. There was silence.

· * ·

Just before 3 p.m. on the afternoon of the same day, 11 June 2014, the family received answers to the proof-of-life question.

‘His parents bought the 2007 apple-green Chevrolet 0.8 from him for 35,000 DKK,’ wrote the kidnappers, who also wanted clarification of where the money was in southern Turkey.

Susanne was happily surprised by all the details about the car that Daniel sent back.

‘He’s understood the message with the green car!’ she said excitedly to Kjeld and wrote in her diary, addressed to Daniel, ‘You responded nicely to our question.’

From then on, Arthur took over the email correspondence. It was now up to him to bring Daniel home.

· * ·

Late at night on 11 June, the first instructions about the handover of the money arrived.

You will make your way to Kilis ASAP.

The kidnappers ordered Arthur to be in Kilis by 4 p.m. at the latest the following afternoon. He was told to constantly keep an eye on his email – ‘BY THE MINUTE’ – and have a yellow taxi waiting on standby until the last instructions were sent.

There were also demands about how the money would be transported: a strong, matte-black rucksack with a padlock on the zipper.

Hostage cases and handovers of ransoms were inherently volatile, but Arthur had never experienced anything like this. The terms came exclusively from ISIS. He felt extremely vulnerable and the exchange had so many risks at play that he stopped counting them.

Arthur lit his pipe. Although it could have consequences, after long consideration he chose to depart from the kidnappers’ instructions on one point.

He rented a white four-wheel-drive vehicle rather than be transported by an unsuspecting taxi driver who couldn’t speak English. He didn’t want to expose other people to the risk associated with handing over €2 million to ISIS.

Furthermore, he could imagine a scenario in which a nervous taxi driver called the police, because he was sitting on an abandoned road along the border with a strange, chain-smoking foreigner in the back seat, who was perhaps about to blow himself up or kidnap him. Arthur couldn’t confide in a random person about his intentions. He at least wanted to be the master of his own means of transport if the terrorists were dictating everything else.

On 12 June at 4.50 p.m. he received further instructions about driving east from Kilis to the town of Elbeyli.

At the beginning of this town there will be a welcome sign that reads ‘Hosgeldin’ and will possibly be worn out and unreadable. Nevertheless, this sign will be your meeting place, WHERE YOU WILL STAY, WAIT AND HAND OVER OUR CASH.

He should arrive at 8.30 p.m and wait until 10.30 p.m. at the latest. Someone would meet him and say the password ‘Turkcell’, to which he would respond ‘Vodafone’.

Arthur waited a little over an hour before answering with a meticulous repetition of the instructions and adding: ‘I have had difficulty finding a taxi driver who I can communicate with and provide detailed instructions to. I would therefore like to ask for your permission for me to come alone in my white 4x4 rental car.’ He added the number plate.

Arthur checked the rucksack with the cash one last time, as well as the satellite tracker that was his only lifeline. It would send a signal every minute to an operations room in the city of Aalborg in Denmark, which was in contact with his backup team, who were on standby two miles from the meeting point. The team included a doctor, who could handle a sudden emergency and would sound the alarm if they received coordinates that indicated Arthur was about to cross the border into Syria.

Arthur drove about six miles to Elbeyli, found his way through the small town and reached the sign that stood near the border. There were no street lights. The only light he could see came from a town some way off.

He parked the car so that it pointed in the direction of Kilis, turned off the engine and wound down the windows so that he could hear if anyone was approaching on foot in the dark. He could just make out a border fence and some vegetation in the rear-view mirror.

Arthur lit his pipe and thought about possible escape routes. At the side of the road heading into town there was a ditch, which he could jump into, but the nearest house was quite far away if he needed to take cover. He had previously studied the area on satellite photos and knew the terrain in his sleep.

The silence was broken only by the cicadas. Arthur waited and stuffed more tobacco into his pipe. The first vehicle he heard rumbling in the darkness was a tractor that was being driven without lights.

It’s probably just a Turkish peasant on his way home, thought Arthur. The next vehicle had its lights on. It was an armoured personnel carrier containing Turkish soldiers coming from the border. If they asked him to move on, Arthur had several explanations ready, about needing a pee and an engine that had stalled. Personally, he thought it looked strange that he had parked right there. The soldiers slowed down and gaped at him, but drove on.

Then he saw a motorcycle tearing up from the border towards Elbeyli at high speed with its headlights off. That drove by, too. A bunch of refugees then appeared out of the dark and stared into the car as they slowly walked past.

Suddenly he heard the motorcycle again. This time it stopped about ten feet from the car. There were two men sitting on it. They were both dressed in black from head to toe, including black ski masks, and Arthur could see they were armed. The engine was idling, while the man sitting behind the driver stepped down. Arthur opened the car door and got out. He had rolled up his shirt sleeves and clearly revealed his palms and arms as proof that he was unarmed as he walked a few steps towards them.

‘Assalamu alaikum,’ Arthur greeted them.

‘Wa alaikum assalaam,’ replied the man who had got off the motorcycle. He was about six feet tall and broad-chested under the black tunic.

‘Turkcell,’ continued the hooded man.

‘Vodafone,’ said Arthur.

Moving slowly, Arthur stuck his arm through the car window and lifted the rucksack off the floor behind the passenger seat. With the ransom money in his hand, Arthur went over to the ISIS fighter and gave him the rucksack. For a moment, the man lifted it, as if to check its weight was equivalent to €2 million.