‘Who the prime minister doesn’t know. If we do anything to draw attention to the Service then he’ll view it as a political move against him.’

‘I don’t much care what Wilson thinks right now,’ Knox said.

‘Well you should,’ Holland replied, a hardness in his voice that Knox rarely heard. ‘It’s your job.’

Before Knox could apologise the door opened and Sarah walked back into the room.

‘The tea lasted all of a minute,’ she said as she sat down on the chaise longue opposite the two high-backed chairs. ‘I’m afraid I had to sacrifice your soup, darling.’

Holland huffed.

‘How is he?’ Knox asked.

‘Like he’s fit to burst or fall apart at any moment.’

She adjusted a pleat in her skirt, an unusual sign of nerves, and smiled at Knox. It was the kind of smile that told him he wasn’t going to like what she was about to say.

‘He’s still Jack, at least most of him,’ she said. ‘He knows who I am, and where he is. But part of him doesn’t. He seems to slip from moment to moment, almost like there’s someone else in there with him.’

‘Someone we don’t know and can’t necessarily trust,’ Holland said, adding a twist to the knife his wife had just politely driven into Knox’s chest.

Knox had to stop himself from jumping to Williams’s defence again.

‘So what can we do?’ he asked.

‘We keep him out of the way,’ Holland replied.

‘He needs our help. We need to know what the Americans did to him, and why someone else is after him.’

‘And we’re going to help him,’ Holland said. ‘Quietly.’

‘Where?’ Knox asked. ‘Whoever came after him today will be watching Kemp House, and Rabley Heath, and he can’t stay here—’

‘Actually,’ Sarah interrupted, ‘maybe he can. He could use the spare room.’

The spare room was Sarah’s name for the heavily fortified fallout shelter that MI5 had clandestinely excavated under Wytchen House in case the Hollands found themselves at home in the event that a nuclear-tipped ICBM crashed into London.

‘Then what?’ This time it was Holland asking the question.

‘Then Richard can take him to the house in Deal for a few days. Take in the sea air, start to recover, spend some time with a familiar face.’

‘I’m not needed for a few days,’ Knox said, jumping on Sarah’s suggestion before Holland could dismiss it.

If the director general wanted to sweep Williams under the carpet, Knox should at least be the one holding the broom. He didn’t want anyone else looking after him or trying to prise what he may or may not know from his addled brain.