‘This is one of the crossroads of the European waterways,’ he said. ‘From here, you can go to Berlin or Hamburg. But you can go much, much further. You can use the Havel and the Oder to take you to the Baltic or into the heart of Poland and the Czech Republic. In the other direction, there’s Rotterdam, Antwerp, Ostende, Paris, Le Havre. Or you can go down the Rhine and the Danube all the way to the Black Sea. And nobody really takes much notice. As long as you have the proper seals on your containers and the appropriate documents, there’s nothing to worry about.’

‘This is how you move your merchandise?’ Carol said, sounding bemused.

He nodded. ‘The Romanians are extremely corruptible. The drugs come across the Black Sea, or else from the Chinese as payment for their travel. The guns come from the Crimea. The illegals come into Budapest or Bucharest on tourist visas. And they all get packed into containers with official customs seals and end up where I want them to be.’

‘You pack people into containers? For weeks at a time?’

He smiled. ‘It’s not so bad. We have containers with special air filters. Chemical toilets. Plenty of water and enough food so they don’t starve. Frankly, they don’t care how bad the conditions are as long as they end up in some nice EU country with a welfare system and a lousy procedure for getting rid of asylum seekers. One of the reasons they love your country so much,’ he added, giving her fingers a gentle squeeze.

‘So you load them all up in the docks on the Black Sea? And everybody turns a blind eye?’ Even with corruptible officials, Carol thought this was a rather chancy operation.

He laughed. ‘Hardly. No, when the containers leave Agigea, they’re full of perfectly legitimate merchandise. But I own a small boatyard about fifty kilometres from Bucharest. Near Giurgiu. The barges pull in there and the loads are … how can I put it? Rectified. The legitimate cargoes are transferred to lorries. And our tame customs officials replace the seals so everything is exactly as it should be.’ He dropped her hand and put an arm round her shoulders. ‘You see how much I trust you, that I tell you all this?’

‘I appreciate it,’ Carol said, trying not to show how overjoyed she was at the precious intelligence she had gained. ‘So how many containers do you have in operation at any given time?’ she asked. It was, she felt, the sort of thing a businesswoman like Caroline would want to know.

‘Between thirty and forty,’ he said. ‘Sometimes there’s only a small amount of heroin on board, but it still means you need access to a whole container.’

‘That’s a big investment,’ Carol said.