“Was anything ever proved against him?”

Guyon shook his head. “It was thought that he was the power behind the scenes in General Chile’s abortive coup in 1961, but there was no evidence. Before any could be collected he asked to be placed on unpaid leave and left France. He’s extremely wealthy, by the way. One of his uncles married into industry after the first war.”

“What does Legrande think about him?"

Guyon laughed. “Legrande has little respect for the aristocracy. He would see the guillotine set up in the old situation and smile at the prospect. He has no proof that de Beaumont it directly connected with the O.A.S., but he is unhappy about him. He would be quite content to see him dead. He has a naturally tidy mind.”

“And what’s your own opinion?”

“Of de Beaumont?” Guyon hesitated. “He’s a dangerous man and no fool. For a year he was in charge of all military intelligence in Algeria, but he was always at loggerheads with the brasshats. He saw war as the Communists see war – as something to be won – and he believed that the end justified the means. Something the boi-dois had beaten into him in the Viet camps.” Guyon half smiled. “This much at least I would expect you to have in common with him. Legrande told me that you, too, were behind the Communist wire for a time.”

“You make him sound interesting,” Mallory said. “I’d like to meet him. I’ve a feeling that would tell me all I need to know.1

“Very possibly.” Guyon emptied his glass. “Is there anything else you wish me to do?”

“This Frenchwoman who’s living at the hotel with Morgan, Juliette Vincente? In my briefing they said she was harmless. What do you think?”

“Our preliminary report certainly didn’t indicate anything unusual. Her mother and father have a small farm in Normandy. One brother, killed doing his military service in Algeria in 1958. She worked at an hotel in St. Malo for six months before coming here.”

Mallory nodded. “Sounds all right, but run the usual check on your room, just to make sure it hasn’t been searched.”

Guyon put on his sun-glasses and got to his feet. “I’ll get changed. See you in about half an hour and we’ll have a look at that reef.5He paused in the doorway and stretched. “It really is a beautiful day. I’m quite looking forward to it.” After he had gone Mallory sat on the edge of the bunk going over things in his mind, trying to work out what might happen, but he knew that he was wasting his time.

If there was one lesson he had learned above all others it was that in this game nothing was certain. Chance ruled every move. He opened one of the lockers, took out the diving gear and started to check it.

mallory vaulted over the rail into the translucent blue water, paused for a moment to adjust the flow of air from his aqualung and swam down in a long sweeping curve that brought him under the hull of Foxhunter to where Fiona Grant swayed beside the anchor chain like some exotic flower in her yellow diving suit. A moment later her sister-in-law appeared beside them in a cloud of silver bubbles.

Fiona jack-knifed at once and followed the anchor chain down into the blue mist, her long hair streaming out behind, and Mallory and Anne went after her.

They were perhaps a hundred yards out from the shore on the southern side of the island and the water was saturated with sunlight, so that even when they reached bottom at forty feet visibility was good.

The sea-bed was covered by a great spreading forest of seaweed six or seven feet deep which moved rhythmically with every ebb and flow of current, changing colour like some living thing. Fiona swam into it, fish scattering to avoid her. Mallory paused, hovering over the undulating mass, and Anne tapped him on the shoulder and moved away.

They plunged over a great black spine of rock and a wall complete with arched Norman window loomed out of the shadows a few feet to the right. Anne swam effortlessly through it and Mallory followed.

It was obvious that only the strong tidal currents on this side of the island had prevented the building from being completely silted over centuries before. It had no roof and the walls had crumbled until they stood no higher than four feet above the sand. Beyond, the sea-bed sloped gently into another forest of seaweed, broken walls and jumbled blocks of worked masonry strewn on every side.

Fiona Grant appeared from the gloom and swam towards them. She poised a couple of feet away, put a hand into the nylon bag which was looped to her left wrist and produced a piece of red pottery which she waved triumphantly. Anne raised her thumb and they all turned, swam back across the rocks and struck upwards to Foxhunter’s curved hull.

They surfaced by the small ladder suspended over the side, and Anne went up first. Mallory followed her, pulled off his mask and turned to give Fiona a hand. She squatted on the deck, taking the pieces of pottery from her bag one by one and laying them out carefully.

Raoul Guyon had set up an easel next to the wheelhouse and was sketching Hamish Grant, who sat in the bows. The Frenchman put down his pencil and moved across to join them.

The General turned his head sharply. “What’s going on?”

“Fiona’s found some pottery,” Anne said.

Guyon turned to Mallory, a strange, alien-looking figure in his webbed feet and black rubber suit. “What’s it like down there?”

“Interesting,” Mallory said. “You should try it.”

“Perhaps later. I’d like to get my sketches of the General finished and the light is just right.”

Fiona unstrapped her aqualung, squatted down on the deck again and started to sort through the pieces of pottery, completely absorbed by her task.

Anne turned to Mallory. “That’s the last we’ll see of her today.”

“Do you want to go down again?”

She shook her head. “I’d like to try out the aquamobiles. You take one and I’ll have the other. We’ll go round the point to the St. Pierre reef. I’ll show you the Middle Passage and there’s at least one interesting wreck.”

Guyon helped Mallory bring the two aquamobiles up from the saloon. They were bullet-shaped underwater scooters driven by battery-operated propellers, designed to operate at depths of up to one hundred and fifty feet. They carried their own spotlights for use when visibility was bad.

Anne and Mallory went over the side and Guyon passed down the heavy scooters. Anne moved away at once, running on the surface, and Mallory went after her.

The sea was calm, the sun bright on the face of the water, but as they approached the great finger of rock jutting out into the sea at the western end of the island Mallory became aware of cross-currents tugging at his body. Anne raised an arm in a quick signal and disappeared.

The sensation of speed underwater was extraordinary. To Mallory it seemed as if he were hurtling through space as he chased the yellow-clad figure in front of him and yet his effective speed was not much more than three knots.

The red nose of the scooter whipped through the blue-green water, pulling him across a jumbled mass of black rocks. For a moment currents seemed to pull his body in several directions at once and then he was round the point and into calmer water.

They surfaced by a weed-covered shoulder of rock and Anne sat on its slope half out of the water and pulled up her mask. On either side, and stretching across to St. Pierre, was white water, surf breaking everywhere over the jagged rocks which made up the central reef mass.

“At low tide most of the reef is twenty feet above water,” she said. “Stretching all the way to St. Pierre like a giant’s causeway.”

“Could it be crossed on foot?”