Martin nodded silently. He’d already considered this possibility. Although he hadn’t changed his private number for years, this was only because there’d been no reason to. Sure, his lawyers knew it, but they’d never published it in any case notes. The billionaire must have excellent sources and deliberately given Gerlinde the file he’d scribbled the number down on.

‘Why are you telling me all of this?’ Martin asked. Turning his back to the doctor, he went over to the porthole. The sun was just setting and the horizon above the sea had a reddish shimmer.

‘To win your trust.’

Martin laughed scornfully. ‘By admitting to manipulating other people?’

‘Yes, I’m an honest soul,’ Yegor laughed. ‘And, hand on heart, I had to use Gerlinde to get you to join us. If Bonhoeffer or I had called, you’d never have come on board.’

‘Did you just say join us?’

‘Yes. I wish to employ you.’

Now it was Martin’s turn to laugh. ‘As what?’

‘As a therapist. Treat our Passenger 23.’

Martin tapped his head. ‘I’m not a child psychologist.’

‘But you did study psychology.’

‘That was a long time ago.’

‘Besides, as a result of your job you know how to deal with traumatised victims. And with people who hide away. Look after the girl. Find out where Anouk has spent the past couple of months.’

Martin pressed his hand against the cold glass of the porthole and shook his head. ‘Why should I help you abduct a child?’

‘Because you don’t have any choice.’

‘Are you threatening to do away with the girl if I go public with this?’

‘Those are your words.’

He fancied he could hear a little dog barking in the background, but couldn’t be sure.

‘Bonhoeffer tells me you haven’t been right in the head since your tragedy,’ Yegor said. ‘But you were compos mentis enough to solve the Anouk Lamar puzzle. And thus your own trauma too, perhaps. Am I not right in thinking you have a vested interest in this case?’

Martin thought of the teddy now in his duffle bag, and looked over at the doctor, who hadn’t moved during the telephone call. She was still standing by the patients’ chair, holding the ampoule, looking like someone out of place at her own party.

‘I think I’m going to notify the authorities.’ Martin said. The doctor gave the slightest of nods. A subconscious gesture of agreement.