"Give me Captain Conde."

"Speaking."

"On your next circuit out to the oil tank get around behind it, then head south at full speed. The Seawitch has been taken over, but I'm sure there's nobody here who can operate the antiaircraft guns. Stop at twenty miles and issue a general warning to all ships and aircraft not to approach within twenty miles of the Seawitch. You have its co-ordinates."

"Yes. But why – "

"Because there's going to be a mighty big bang. Christ's sake, don't argue."

"Don't argue about what?" a voice behind Mitchell said.

Mitchell turned round slowly. The man behind the pistol was smiling a smile that somehow lacked a genuine warmth. Greenshaw had been pushed to one side and the gun moved in a slow arc covering them both. "I got a hunch Gregsoa would like to see you both."

Mitchell rose, turned, half-staggered and clutched his right forearm inside the sling. Greenshaw said sharply: "God's sake, man, can't you see he's ill?"

The man glanced at Greenshaw for just a second, but a second was all that Mitchell required. The bullet from the silenced .38 took the gunman through the heart. Mitchell peered through the doorway. There was a fair degree of shadow there, no one in sight and the edge of the platform not more than twenty feet away. A few seconds later the dead man vanished over the edge. Mitchell and Greenshaw returned to the main body of the company via the sick bay. Cronkite and Gregson were still in deep discussion. Larsen stood some distance apart, apparently in a state of profound dejection. Greenshaw approached him and said quietly: "How do you feel?"

"How would you feel if you knew they intended to kill us all?"

"You'll feel better soon. Round the back of the building, when you get the chance, you'll find some hand grenades which should rest comfortably inside that lumberjacket of yours. You'll also find two loaded Schmeissers. I have a few grenades in my bag here. And Mitchell has his .38 inside his sling."

Larsen took care not to show his feelings. He looked as morose as ever. All he said was: "Boy, oh boy, oh boy."

Lord Worth was on his feet now, supported by his daughter. Mitchell joined them. "How do you feel?"

Lord Worth mouthed his words with understandable bitterness. "I'm in great shape.”

"You'll feel better soon." He lowered his voice and spoke to Marina. "When I give the word, say you want to go to the ladies' room. But don't go there. Go to the generator room. You'll see a red lever there marked 'Deck Lights.' Pull it down. After you count twenty, throw it back on again."

Cronkite and Gregson appeared to have finished their discussion. From Cronkite's smile it appeared that his view had prevailed. Lord Worth, Marina, Larsen, Greenshaw and Mitchell stood together, a forlorn and huddled group. Facing them were the ranks of Cronkite, Mul-hooney, Easton, and the bogus Colonel Farqu-harson, Lieutenant-Colonel Dewings, Major Breckley, Gregson and his killers, a formidable group and armed to the teeth.

Cronkite spoke to a man by his side. "Check."

The man lifted a walkie-talkie, spoke into it and nodded. He said to Cronkite: "Charges secured in position."

"Excellent. Teh1 them to go due north for twenty miles and stay there." This was done. Unfortunately for Cronkite, his view to the west was blocked by the shattered building behind him and he could not see that the Roomer was already proceeding steadily to the south.

Cronkite smiled. "Well, Worth, it's the end of the road for both you and the Seawitch." He dug into a pocket and produced a black pear-shaped metal container. "This is a radioactive detonating device. Note this small switch here. It's supposed to be good for sixty minutes, but I have already run off ten minutes of it. Fifty more minutes and poof: the Seawitch, you, Worth, and everyone aboard will be vaporized. Nobody's going to feel a thing, I assure you."

"You mean you intend to kill all my innocent employees aboard the rig? Cronkite, you are stark raving mad."

"Never saner. Can't have any witnesses left to identify us. Then we destroy two of the helicopters, cripple your derrick crane, smash your radio room and take off in the other two helicopters. You could, of course, figure on jumping into the Gulf, but your chances of survival would be about the same as a suicide jumping off the Golden Gate Bridge."

Mitchell nudged Marina. She said in a faint voice: "May I go to the ladies' room?"

Cronkite was joviality itself. " 'Course. But make it snappy."

Fifteen seconds later the deck lights went out.

In the end it was Mitchell, with his extraordinary capacity to see in the dark, who ran round the corner of the shattered building, retrieved the two Schmeissers – he didn't bother about the grenades – returned and thrust one into Larsen's hands. In eight seconds two men with submachine guns can achieve an extraordinary amount of carnage. Larsen was firing blind but Mitchell could see and pick out his targets. They were helped in a most haphazard fashion by Dr. Greenshaw, who flung grenades at random, inflicting even more damage on the already shattered building but not actually injuring anyone.

The lights came on again.

There were still seven people left alive – Cron-kite, Mulhooney, Easton, Gregson and three of his men. To those seven Mitchell said: "All right, drop your guns." Shattered and stunned though the survivors were, they still had enough wits left to comply at once.

Marina arrived back and was promptly sick in a very unladylike fashion.

Mitchell put down his Schmeisser and advanced on Cronkite. "Give me that detonating device."

Cronkite removed it slowly from his pocket and lifted his arm preparatory to throwing it over the side. Whatever else, it would have meant the destruction of the Seawitch. Cronkite screamed in agony as the bullet from MitchelTs .38 shattered his right elbow. Mitchell caught the detonating device even before it could reach the deck.

He said to Larsen: "Are there two absolutely secure places, with no windows and iron doors, which can be locked without any possibility of opening them from the inside?"

"Just two. Safe as Fort Knox vaults. Along here."

"Search these guys and search them thoroughly. Make sure they haven't even got a penknife."

Larsen searched. "Not even a penknife." He led them to a steel-reinforced cell-like structure and he and Mitchell ushered them inside.

In spite of his agony, Cronkite said: "You're not going to leave us in here, for God's sake!"

"Same as you were going to leave us." Mitchell paused, then added soothingly: "As you said, you won't feel a thing." He closed the door, double-locked it and put the key in his pocket. He said to Larsen: "The other cell?"

"Along here."

"This is madness!" Lord Worth's voice was almost a shout. "The Seawitch is safe now. Why in God's name destroy it?"

Mitchell ignored him. He glanced at the timing device on the detonator. "Twenty-nine minutes to go. We'd better move." He placed the device on the floor of the cell, locked the door and sent the key spinning far out over the Gulf. "Get the men out of the occidental buildings, and out of the sensory, radar, sonar and radio rooms and make sure that all the helicopter pilots are safe." He glaaced at his watch. "Twenty-five minutes."

Everyone moved with alacrity except for Lord Worth, who merely stood with a stunned look on his face. Larsen said: "Do we need this mad rush?"

Mitchell said mildly: "How do we know that the settings on that detonator are accurate?"

The mad rush redoubled itself. Thirteen minutes before the deadline the last of the helicopters took off and headed south. The first to land on the Roomer's helipad held Mitchell, Larsen, Lord Worth and his daughter, in addition to the doctor and several rig men, while the other helicopters still hovered overhead. They were still only about fourteen miles south of the Seawitch, which was as far as the Roamer had succeeded in getting. But Mitchell reckoned the margin of safety more than sufficient. He spoke to Conde, who assured him that every vessel and aircraft had been warned to keep as far away as possible from the danger area.