Duddingston Village was just that – a village in the midst of a city, sheltering beneath Arthur’s Seat. Duddingston Loch – more outsize pond than true loch – looked down on to a bird sanctuary and a path known as the Innocent Railway: Rebus wished he knew where it got the name.

Jack stopped the car and flashed his lights. Mairie switched hers off, unlocked her door, and came loping towards them. Rebus leaned into the back to open the door, and she got in. He introduced her to Jack Morton.

‘Oh,’ she said, ‘you worked the Knots and Crosses case with John.’

Rebus blinked. ‘How do you know that? It was before your time.’

She winked at him. ‘I’ve done my research.’

He wondered what else she might know, but hadn’t time to speculate. She handed him a brown A4 envelope.

‘Thank God for e-mail. I’ve a contact on the Washington Post and he got me most of what’s there.’

Rebus switched on the interior light. There was a spot-lamp specially for reading by.

‘Usually he wants to meet me in pubs,’ Mairie told Jack, ‘right seedy ones at that.’

Jack smiled at her, turned in his seat with his arm hanging down over the headrest. Rebus knew Jack liked her. Everyone liked Mairie from the off. He wished he knew her secret.

‘Seedy pubs suit his personality,’ Jack said.

‘Look,’ Rebus interrupted, ‘will you two bugger off and go look at the ducks or something?’

Jack shrugged, checked it was OK with Mairie, and opened his door. Alone, Rebus settled deeper into his seat and started to read.

Number one: Major Weir was not a Major. It was a nickname, earned in adolescence. Two, his parents had handed on to him their love of all things Scottish – up to and including a craving for national independence. There were a lot of facts about his early years in industry, latterly the oil industry, and reports of Thom Bird’s demise – nothing suspicious about it. A journalist in the States had started writing an unauthorised biography of Weir, but had given up – rumour had it he was paid not to finish the book. A couple of stories, unsubstantiated: Weir left his wife amid much acrimony – and later, much alimony. Then something about Weir’s son, either deceased or disinherited. Maybe off in some ashram or feeding the African hungry, maybe working in a burger parlour or Wall Street futures. Rebus turned to the next sheet, only to find there wasn’t one. The story had finished mid-sentence. He got out of the car, walked to where Mairie and Jack were in huddled conversation.

‘It’s not all here,’ he said, waving what sheets he had.

‘Oh, yes.’ Mairie reached into her jacket, brought out a single folded sheet and handed it over. Rebus stared at her, demanding an explanation. She shrugged. ‘Call me a tease.’

Jack started laughing.

Rebus stood in the glare of the headlights and read. His eyes widened and his mouth fell open. He read it again, then for a third time, and had to run a hand through his hair to make sure the top of his head hadn’t just blown off.