‘They say there are two paradoxes in blackmail,’ said Casey, almost to herself. ‘Revealing a secret is legal, and asking for money – or whatever else – is legal. But when you do both simultaneously, it becomes a crime. And the other paradox is that if the blackmailer initiates the sequence, it is illegal. But if the blackmailee asks for secrecy in return for money – it is the chief executive who groped the secretary who makes the offer – then it is legal. Odd aren’t they, the economics of secrecy?’

‘Two rights make a wrong,’ said Ed. ‘Two wrongs make a right.’

‘I suppose so. Yes.

I’ve upset Hessa.’

‘I thought so.’

They watched two ships track across the horizon. One heading north, the other heading south, red and green lights flashing.

‘I suppose,’ Ed said, as the lights crossed over, ‘those ships are the reason we first met.’

The memory stabbed at Casey. That night, all those years ago, out on the wilds of the Indian Ocean. Sitting on a pile of ropes on the deck of the Apollo, idly watching the captured Somali pirates.

‘I have no idea how they get on board those huge supertankers,’ Ed had said then. ‘The risks they take to survive. Those big ships go like the clappers through the risky areas now, and the wake they generate is crazy. How do you get close enough in a tiny little boat?’

‘Wilful determination?’ Casey wondered aloud.

‘Supertankers are designed not to have access points below a certain height,’ said Ed. ‘The pirates are looking up at, say, ten storeys of steel. But they zoom along in those tiny boats and just go for it.’

‘It should be impossible.’

‘You should see the official guide to defending yourself from pirates,’ Ed had said. By then, he was enjoying speaking to her, she could tell. ‘Issued by the authorities. They recommend barbed wire. And they note, quite politely, that pouring boiling water over the side of the ship can be helpful too.’

‘It sounds medieval,’ Casey had said.

‘It is, really.’

The sun was a line of fire over the Bay of Bengal. Ed pulled Casey to her feet. ‘Let’s go for a walk.’

Talking quietly, they wandered down the beach. The straggle of high-rise hotels slowly fell away, leaving just the coast road, and a fringe of palm trees.

The sunset, the beach, the whispering palms. For a second, Casey saw Ed’s profile dark against the sky, and spiralled into the impossible.

‘How can you work for Declan Bentley?’ Casey forced the thoughts away.

‘There aren’t that many billionaires with a perfectly clean sheet,’ Ed protested. ‘I like the south of France. I get on fine with Declan. I know he comes across as a prick, but compared to some . . .’

‘But his factory in Ethiopia,’ Casey protested. ‘And God knows what the new Vietnamese factory is like.’