Knox cleared his throat and said, ‘Did James ever tell you about my parents?’

She sighed. ‘You really do think the world revolves around you, don’t you?’ Her voice was sharp. ‘I don’t care about you or your parents. I care about my husband.’

‘How is he?’ Knox asked.

‘No change. They say that’s a good thing, as if it could possibly be.’ She checked her watch. ‘I’m due there in an hour.’

‘I just need five minutes,’ Knox replied. ‘It’s about James.’

Knox watched Sarah check the temperature of the teapot with the back of her hand.

‘Fine. Five minutes,’ she said, marking her page and closing the book.

‘It’s about James,’ he said again, ‘but it starts with my parents. They were normal people. Normal for the East End. My father was a labourer, my mother took in sewing. They got by, until I came along and the economy went to hell. Work dried up. Sometimes there was no money. Sometimes there was no food.’

Knox knew Wytchen House had been in Sarah’s family for over a hundred years. He wondered whether the hard times of the thirties had even touched her and the other residents of Highgate.

‘They survived,’ he continued, ‘hanging on day after day, just like everyone else around them. But eventually things got too hard and people gave up. I don’t mean they left. I mean they died. Starved, or got sick and couldn’t get better. The East End had become a ghetto and people were being left to. rot in it. It drove my parents mad.’

He paused for a moment, shifting his weight on the chaise longue. He knew he could end his story here and protect Sarah from the secret he and her husband had shared for so long. But he also knew he couldn’t.

‘There was an old builders’ yard near our house,’ he said. ‘It had been shut up and forgotten about. One day my father broke in, looking for tools or something he could sell. He found a locked box tucked away inside a cabinet. There were two sticks of dynamite inside.’ He lowered his eyes to the rug in front of him. ‘My parents weren’t anarchists. They were desperate and stupid. They just wanted to get people’s attention, make them see how bad things had got. They decided to blow a hole in the wall of a police station. But they didn’t know how powerful the dynamite was. Or how quick the fuses would burn. Two policemen died in the explosion, along with my parents.’

He looked up, his eyes meeting Sarah’s again. She hadn’t moved. The hardback was still clutched in her lap.

‘James knew about this?’ she asked.