Hessa managed to keep her face expressionless. ‘It might be partly because of the perception of the Rohingya in Bangladesh,’ she said lightly. ‘They’ve been denied everything – education, basic human rights, homes – for decades. In the last few years, hundreds of thousands of Rohingya have been trafficked into slavery. Certain Bengalis would find it odd, the idea of negotiating with them.’

‘Fine,’ Dash shrugged. ‘Easier to snatch than to pay.’

Hessa stared at him. ‘Something like that.’

‘OK,’ said Dash, after a pause. ‘Spend some time working on it if you want. But you haven’t got much to go on, you know.’

Dash’s mobile rang. It rang every few minutes, all day, all night. He ignored it.

Casey glanced across at him. ‘We’d have to find the clients in the West,’ she said slowly. ‘Find out who is coordinating it all. And where they are.’

Her eyes were hazy now, the calculations almost blurring her sight.

‘And none of that,’ said Dash, ‘will be easy.’

He stepped out of the room, leaving a silence behind him.

‘He’s worried about you, you know,’ Miranda said to Casey.

‘I know,’ Casey shrugged. ‘I know. But I am fine.’

They sat in the small office for hours.

‘Right,’ Miranda began. ‘Let’s work out how we would do it.’

One of the old reporters at the Sunday Times had explained that trick to Miranda after the fourth bottle. Put yourself in their head. Work out what you would do, and then flip it.

And he – half crook himself – had tracked down rogue after rogue.

‘Where would you find the clients in the first place?’ Miranda asked ‘In London?’

‘Wimpole Street?’ said Casey. ‘Harley Street?’

Patients flew from all around the world to those elegant Georgian roads cutting through the heart of Marylebone. Where Elizabeth Barrett searched for a cure, and only ever found love.

Rhinoplasty and ophthalmology, dermatology and podiatry. There was no part of the body that couldn’t be tweaked, so carefully, with a soothing smile. Hundreds of doctors worked along those streets, most expensively.

Most discreetly, too, behind their little brass nameplates.

‘But where would we start?’ said Casey. ‘There must be dozens of places that offer fertility treatment on Harley Street alone. How could we guess the right one?’

‘You’d probably have to go through all sorts of hurdles first too,’ Miranda thought aloud. ‘It’s not the sort of thing you’d be offered on your first appointment, surely? Unless, maybe, if we asked the right questions . . .’

‘We could ask about surrogacy,’ suggested Casey. ‘And just see where that led.’

‘Or perhaps someone in India is referring clients on to Bangladesh?’ suggested Hessa. ‘After the surrogacy programmes got shut down in India?’

‘Because we’re not even sure if the scheme only operates in London,’ said Miranda, drawing doodles. ‘Whoever put that message in the skirt might be sending others to Germany, Australia, wherever.’