You are what you are when no one is looking. He turned and blinked at Dyer as if he hardly recognised him. His hair seemed more matted, his eyes duller. He had the face of a derelict, one of the homeless men on the pavement outside Blackfriars whom Dyer passed every morning, invariably staring at a book upside down in the hope that Dyer would mistake them for a former student whom life had unfairly elbowed into the gutter.

‘It’s me,’ Dyer had to remind him. ‘Leandro’s father.’

Marvar scratched his arm. His coat was on tight, he had done up every button.

‘John Dyer …’

His breath, visible, mingled with the smoke leaving his nose. He was not himself. It was as if something dreadful had happened to him.

‘Are you coming to the football match?’ said Dyer. ‘I can give you a lift.’

Marvar threw away his cigarette and clutched Dyer’s arm.

‘No, no, I can’t.’ He looked directly at him. Behind his glasses, there was a dancing flicker in his eyes. ‘Dyer … have you a second?’

It occurred to Dyer that Marvar’s behaviour might be connected with the news about Iran. He checked his watch. The match began in forty minutes.

‘Listen …’ he decided. ‘My place is around that corner, literally. We can go there.’

He would hear what Marvar had to say. If he drove fast, he could still arrive in time.

With an odd sudden tilt of his face, Marvar glanced both ways up Great Clarendon Street. There was a silver Golf parked on the other side, its windows fogged up. He gave it a nervy look.

‘Yes, yes. All right.’

He walked in quick strides beside Dyer, breathing in gulps.

Dyer showed him in. It was the house where he had lived for a year and a half: tiled floors, the pâté-coloured staircarpet. From the window in the small sitting room, you could see the canal. The landlord lived in Wolvercote, and favoured round white doorknobs from Homebase and white crockery.

Converted from a garage, the place was not to everyone’s taste, with its creaking furniture and single-glazed windows that rattled in a hard wind, letting in the sound of trains. The upstairs smelled of new carpet, and the radiators emitted a sharp gurgling noise when the heating came on. At the rear, French windows opened onto a courtyard with a wooden tub containing a magnolia.

Marvar tripped over the two bicycles in the hallway, and sent Dyer’s fishing rod clattering. Balance regained, he stumbled into the kitchen area.

Dyer propped the rod back up and waited for him to finish unbuttoning.

‘Have a seat.’ He took Marvar’s coat and went to hang it up in the cupboard under the stairs, next to his tackle.

Re-entering the room, ‘Tea? Coffee? Something stronger?’ On the draining board was a glass with a red halo at the bottom.