‘Here we are,’ Sanders said as they entered St John’s Wood and turned into Marlborough Place. There had been little conversation on the drive back. It struck Hepton that the two of them had nothing in common, and that if they had not been thrown together like this, they would never have chosen one another as companions.

‘Hold on,’ Sanders said in warning as the car approached the house. His eyes had narrowed to slits, his face close to the windscreen.

‘What is it?’ Hepton was looking, too, but could see nothing out of place. Sanders drove past the house without stopping. ‘What is it?’ Hepton repeated in a low hiss.

‘Too many lights on.’

‘What?’

‘All the lights inside the house are on. So is the light outside the front door, and the one to the side of the garage. It even looks as though there might be lights on in the garden.’

‘So?’ Hepton didn’t want to think about what Sanders might be implying.

‘So, something’s wrong.’ He pulled the car in to the kerb and stopped, shutting off the engine and killing the lights.

‘What are we going to do? Just wait here? Jilly’s in there! We can’t—’

But Sanders was staring at the number plate of the car parked in front of them. The car itself was a Vauxhall Cavalier like his. He seemed not to have heard Hepton’s outburst.

‘Funny,’ he said. ‘That’s Thommo’s car.’

‘Thommo? Who’s Thommo?’

‘The other lot. MI5. He’s one of their … well, men.’ He stared at Hepton, his face draining of colour. ‘We better go in, but slowly. Keep with me.’

They opened the car doors and closed them – as Sanders instructed – quietly. Sanders was already pulling his gun from its holster as they approached the house. Hepton was frantic now. What had happened? There was no one to meet them at the front door, no guard. Sanders pushed open the door. There were voices coming from within, though muted. Everyone was being very quiet indeed. Then someone came into the hall, saw them, and turned his head back into the living room.

‘Sir,’ he called. ‘Visitors.’

Another man, balding but not yet middle-aged, his moustache thickly black, popped his head into the hall, stared at Hepton and Sanders, then lifted his eyes towards the ceiling and gave a great groan of relief.

‘Sanders, you bastard. Thank God. I thought they’d got you.’

Sanders was slipping his pistol back beneath his arm. He had become very businesslike, his voice like something lifted from cold storage.

‘Fill me in,’ he said.

The man looked from Sanders to Hepton, then back to Sanders. Sanders turned towards Hepton, who knew what he was going to say and cut in first.

‘I’m not leaving. I’ve got a right to hear it too.’ He looked at the man. ‘Is Jilly all right?’