Caleb sat very still in his chair for a moment. Then looked from his father to me and back again, a decision working itself out in his face. ‘I bet you would, I bet you would,’ he said, also to the beat.

The front feet of Langdon’s chair hit the plywood floor hard. ‘I’m not sure I like your tone, Caleb.’

‘And I’m not sure I care,’ Caleb answered. This time his sideways look took in Amelia as well as me. He drew a deep breath and pulled his shoulders back. ‘Let Jack and Amelia go,’ he said simply.

‘Or?’ said Langdon.

Caleb rose from his chair. Quietly but forcefully he laid down one word: ‘Else.’

My uncle carries the ominous swell of good living beneath his Hawaiian shirts. But although a little out of shape, he has as much weight in his shoulders as his gut, muscled forearms, a rugby-player’s thighs. He got up slowly from his chair and stood toe to toe with Caleb. They matched each other in height; if anything Caleb was the taller. But although gym-built, my cousin could not have been more than two-thirds of his father’s weight. Breathing heavily, Langdon said, ‘Repeat that. I dare you.’

‘You don’t get it, do you?’ said Caleb.

He opened his mouth to go on, but before he could, his father hit him. It wasn’t a punch – Langdon’s hand was open – but all the same it was a heavy blow out of nowhere, a backhander flung hard. Caleb’s head snapped sideways and he staggered backwards. But his feet were quick beneath him, and as soon as they’d stopped him falling they drove him straight back at Langdon. I couldn’t believe what I was seeing. With real speed Caleb fired three punches at his father. The first caught him square beneath the solar plexus. Langdon dipped forward in astonishment as the second, an upper cut, glanced off his jaw. The third punch was a straight jab, square in the face. Langdon dropped to his knees, a hand covering his nose. For a second nothing happened. Then he looked up. His nose and chin were already awash with blood. Caleb took a step forward and stared down at his father. He looked electric with anticipation, simultaneously aghast and ecstatic at what he had done.