they were close to the island now and Marcel cut the engine to half-speed and took Foxhunter in slowly towards the dark arch. The speedboat bobbed behind them on a long towline and as Mallory looked out to sea a shadow moved in from the horizon, blanketing the stars.

Guyon stood by the rail a few feet away talking to de Beaumont in a low voice and Jacaud leaned against the wheelhouse, the sub-machine-gun in his hands. One of his eyes was half-closed, the right side of his face swollen and disfigured by a huge purple bruise, and his eyes stared at Mallory unwinkingly.

They moved into the dark entrance and Mallory shivered, chilled by the damp air, and then they were through. From end to end the cave was about a hundred yards long and perhaps fifty feet across. Beneath the surface, as he had discovered earlier, it was even wider.

The long stone jetty was brightly illuminated by two arc-lamps and they coasted in to tie up behind a magnificent forty-foot, steel-hulled motor-yacht, the name Fleur de Lys painted across her counter.

The submarine was moored on the far side, squat and black in the water, and looked even smaller than Mallory had imagined. A dozen or so men in the uniform of the French Navy worked busily, loading stores on board under the supervision of a slim, rather boyish-looking lieutenant in peaked cap and reefer jacket. As they went up the short ladder to the jetty, he came forward, saluting de Beaumont casually.

“How are things going, Fenelon?” de Beaumont asked. “Any snags?"

Fenelon shook his head. “We’ll be ready on schedule.”

“Good, I’ll give you a final briefing at 9 a.m.” Fenelon went back to his men and de Beaumont turned to Mallory. “Magnificent, isn’t she? And just the thing for our purposes. Small, compact – only needs a crew of sixteen. You’re familiar with the type?”

“Only on paper.”

“This one has quite a history. Built at Deutsche Werft in 1945 and sunk with all hands within a month of commissioning. After she was raised she was transferred to the French.”

“And now she’s yours,” Mallory said. “A chequered career.”

A body was against the far wall covered by a tarpaulin, webbed feet turned to one side, blood streaking the pool of sea-water in which it lay.

“We couldn’t find the other one. The current must have taken him under the reef.” De Beaumont shook his head. “A nasty way to die.”

The words seemed to carry an implicit threat, but Mallory refused to be drawn, and de Beaumont smiled faintly and led the way across to where a flight of stone steps lifted a hundred feet into the gloom, curving round one wall of the cave. They mounted the steps and emerged on to a stone landing, and de Beaumont led the way to the far end of a passage, passing several doors. One or two stood open to show narrow service bunks and grey blankets neatly folded. From a side entrance there came the smell of cooking.

He opened another door and they entered a large hall, great curved beams of oak arching into the gloom. There was a wide marble staircase and, above it, a gallery. At one side logs blazed in an immense medieval fireplace.

“Quite a sight, isn’t it? The money these Victorian industrialists must have had to throw around, and every stone brought in by boat.”

His tone was casual, mannered. He might have been a rather complacent host showing a friend over his new place. They went up the great staircase and moved along the gallery to the far end. De Beaumont opened a door to disclose a narrow spiral staircase. At intervals there were slotted windows and Mallory could see far out to sea as they mounted higher and higher.

They reached a stone landing and paused outside a door. De Beaumont went in, leaving it ajar. The room contained a great deal of radio equipment and an operator sat before a transmitting set, headphones clamped to his ears. He stood up when de Beaumont appeared. There was a murmur of conversation and then the Colonel came back outside.

He continued up the spiral staircase, Mallory, Guyon and

Marcel following behind, Jacaud bringing up the rear. At last they emerged on a small landing and de Beaumont opened his final door.

The room was circular in shape and quite large. It was comfortably furnished, Persian carpets covering the floor, logs burning brightly in the wide fireplace. The walls were lined with books except for a section perhaps twenty feet long covered by a velvet curtain. De Beaumont pulled it to one side, revealing a curved glass window.

“One of my little improvements. On a clear day you can see France.” He indicated a chair by the fire. “If you please.”

Mallory sat in the chair and Jacaud moved to stand behind him, the sub-machine-gun held ready. Marcel stood by the window, a revolver in his right hand held against his thigh. Guyon remained by the door and Mallory looked across at him. Guyon returned his gaze calmly, giving nothing away, and Mallory turned to de Beaumont, who was now sitting in the opposite chair.

“I will not insult your intelligence by fencing with you, Colonel Mallory,” he said. “For some time I was a prisoner of the Viets in Indo-China. There is little they failed to teach me at first hand about the extraction of information from the uncooperative. Jacaud was senior warrant officer of my regiment. He shared my experiences. I need hardly add that he would welcome an opportunity to experiment.”

“No need to go on,” Mallory said. “I get the point.”

“Excellent,” de Beaumont said. “We can get down to business. As you may now have deduced for yourself, Captain Guyon is something of a double agent. When the Deuxieme offered him employment they were not aware that he was already a loyal member of the O.A.S. A most convenient arrangement. He confirms the fact that the Bureau had no real grounds for suspecting L’Alouette to be in hiding here. That his assignment to lie de Roc to work with you was at the request of British Intelligence. I’d like to know why.”

“We had a man here watching you,” Mallory said. “Just routine, because of who you are and what you are. He drifted in on the tide the other evening. Accidental drowning was the coroner’s verdict.”

“He had a habit of taking long walks on the cliffs after dark with a pair of night-glasses,” de Beaumont said. “Rather dangerous. Someone should have warned him.”

“You made a mistake there,” Mallory said. “To my chief it meant only one thing. Our man had seen something important. With the French combing every creek and inlet on their side of the Channel it gave him a rather nasty feeling to think that she might be sitting it out in the Channel Islands.”

“A pity,” de Beaumont said. “Now I must move out rather sooner than I had intended. On the other hand, neither my immediate nor long-term plans will be affected in the slightest.” He stood up and smiled politely. “Under happier circumstances I should have enjoyed talking to you. We must have a great deal in common. I’m sure you’ll understand that my time is limited.”

“Naturally,” Mallory said ironically and got to his feet.

He had often wondered about this moment, how it would come and when. The strange thing was that he was not afraid. More curious than anything else. Jacaud moved restlessly behind him and Marcel came away from the wall, the gun still held against his leg.

De Beaumont took a revolver from his pocket, crossed to Guyon and handed it to him. “Will you do the honours, Captain? A soldier’s end, I think.”

Guymon’s hand tightened on the butt of the revolver and he looked across at Mallory, his face very white. Quite suddenly he grabbed de Beaumont by the front of his coat, pulling him forward, and rammed the barrel of the revolver against his throat.

There was a moment of stillness and then de Beaumont laughed gently. “You know, our friends in Paris have been worried about you for some time now, Guyon. I can understand why. You’re slipping. I should have thought an officer of your experience would have been able to tell the difference in weight between a revolver loaded with blanks and one loaded with live ammunition.”