They came to a security door. There were numbers on its handle, and the man pressed three of these before turning the handle itself. In this new corridor, things were quieter, cooler. There was a slow hum of air conditioning, the low sounds of distant voices. They came to a final door, and the man opened it, gesturing for Dreyfuss to precede him into the room. A very attractive young woman sat on a chair, watching a bank of TV screens, switching between surveillance of one part of the base and another. One side of her face was heavily made up.

The door closed solidly behind Dreyfuss, and when he turned, the man was pointing a Beretta pistol directly at his chest.

‘The guard was right,’ he told the woman, who had risen to her feet. ‘Someone did take Peter Fulton’s pass, unaware that Fulton flew off on holiday yesterday.’ Dreyfuss’ heart sank. ‘I recognised him as soon as I saw him,’ the man continued. ‘Major Michael Dreyfuss, isn’t it?’

‘At your service,’ Dreyfuss said softly. ‘And you are …?’

‘Didn’t I say?’ The man had come round to stand beside the woman. He bowed his head slightly, but the pistol never wavered. ‘I’m George Villiers; you may have heard of me. And this is Harry.’

On hearing Dreyfuss’ identity, a keen look had come into Harry’s eyes. She examined him as though he were some rare species, some rare and endangered species.

‘Where’s Jilly?’ Dreyfuss asked, his voice as brittle as a thread of ice.

Villiers ignored him. ‘Harry,’ he said, ‘Major Dreyfuss came into the station with another man. I went and took a look at the main door just to be sure, and I was right – guess whose pass is missing all of a sudden?’

‘Whose?’ Her voice was soft and feminine.

‘Martin Hepton’s.’

The laugh was cavernous beyond her slender frame. She went to the desk and lifted an attaché case onto its surface. The locks clicked, and she pulled the case open. Inside was the most lethal-looking handgun Dreyfuss had ever seen. It resembled a heavily modified target pistol, with a long shining silver barrel. There was a sight in another compartment of the case’s moulded interior, and she fixed this along the pistol. Then she closed the case again and brought a plastic carrier bag out from the bottom drawer of the desk, placing it over her left hand, which was now grasped around the carved butt of the gun. It didn’t quite look as though she were merely carrying an empty bag, but the gun was sufficiently disguised. She touched the fingers of one hand to the scald marks on her face. Finally, wordlessly, and on silent feet, she walked to the door, opened it and left, closing it behind her.

Dreyfuss looked at Villiers, who appeared impressed by the performance. ‘Where’s Jilly?’ he repeated.