‘Near Sedburgh.’ She looked at Dyer. ‘With that accent thy’s not a southern soft either.’

‘Too right I’m not.’ His mother’s family were from Clitheroe. They hardly ever crossed the Shap Divide to go up to Penrith, he told her. His grandmother viewed everyone not from their region as an ‘off-comer’, could barely bring herself to speak to them.

Her turn to smile. ‘You don’t seem very keen, either, to share what you know. Maybe once you have the full picture, you’ll see why it’s so important that you help us as much as you can.’

Left alone with Dyer, Hissop said to him: ‘Iran. Ever been there?’

No, said Dyer, but there was a time when his newspaper had wanted to send him, and he was tempted. In the 1950s, an English poet he admired had served in Tehran as the Times’s special correspondent, until his expulsion.

Hissop had not heard of Basil Bunting. He brushed the crumbs off his shirt. ‘Time I was there, it wasn’t very funny either. I tell our chaps: Don’t lose your temper. Count to ten on lots of occasions. If you say: “Listen I’m not going to pay you, you arrogant bastard, because you’re lazy and corrupt,” you’re not going to get over the border in a hurry, but this is what our American friends tend to do and wonder why they’re not home in time for dinner.’

‘What were you doing there?’

‘Long story, don’t worry about it. But you’ve worked in South America. You know the smell of the lonely roads at night.’

Presently, Updark returned. He retrieved from his jacket the small spiral-bound notebook in which earlier he had entered Dyer’s answers, and glanced at it. ‘Where were we? Oh, yes, you were saying Marvar didn’t give you anything.’

‘That’s not quite true,’ said Dyer. ‘He did leave his overcoat behind. I’ve been wondering how to return it. If he’s gone missing, that explains why I haven’t heard from him.’

The unstiffening was minuscule, but Dyer detected a relaxation in Updark’s response, as if he was quite pleased that Dyer had mentioned the overcoat. ‘You have no inkling where he might be?’

‘None at all.’

‘These physicists love to go hiking,’ said Hissop, somewhat joylessly. ‘They say it’s good for clearing their minds,’ and he read out the names of four scientists and their favourite mountain ranges. ‘Did Marvar mention any hiking?’

‘What, in February? Without his coat?’ Dyer laughed. He wasn’t going to tell them about Ullswater, and he could be reasonably certain that Marvar hadn’t told anyone else. ‘You’ve seen him,’ appealing to Updark. ‘He’s an alien to all forms of physical exercise, I’d have thought.’