They reached the stairway to the cargo pier, climbed up past the submarine, and then turned into the corridor that led to the control deck at the far end of the pen.

"Well, Pat, we've got this far," Lanyon said, as they paused in the corridor to regain their breath. He pulled the torch from his jacket, switched it on.

"Doesn't look as if there's anyone around, Steve. Do you think the _Terrapin_ will still be here?"

"God knows. If not, we'll come back and sit the storm out in the big K-boat."

They reached the control deck, peered into the abandoned offices. The heavy concrete walls of the base were still holding without any difficulty, but somewhere a ventilator had collapsed and air poured through the vents, blowing the papers off the desks and shelves. Litter lay everywhere, drawers pulled out, water dispensers smashed, broken suitcases strewn about the floor.

"Left in a hurry," Lanyon commented. "Seems to me that this is a pretty good place to sit tight. Where the hell have they all gone?"

They hurried along the dark communications corridor, crossing the control decks of the next three pens. As they passed the fifth the floor suddenly shifted slightly, and Lanyon tripped and collided with the wall.

"Good God, don't tell me it can move even this place! The sea must be breaking over the entrance to the pen, driving the whole unit back into the shore."

"Come on, Steve, let's hurry," Patricia said. She held onto his arm as they ran down the corridor. They stumbled into the last control deck, dived down the stairway into the cargo depot. As they reached the bottom the door out into the jetty opened, lights flooded on and two sailors peered round. They gaped at Lanyon and Patricia, clothes ripped to shreds, covered with thick mud up to their waists, Lanyon's bruised face barely recognizable under his beard. Their hands moved to the revolvers in their holsters, and then one of them jumped to attention and snapped out a salute.

He swung his head through the doorway, shouted out:

"Attention there! Commander Lanyon to come aboard!"

Lanyon put a hand out and squeezed the man's shoulder gratefully, then stepped through onto the narrow pier.

Deep water boiled and swirled into the sub-pen through the open gates, surging down to the far wall 200 yards away.

Riding high on it, deckwork trim, periscopes aligned, was the _Terrapin!_

Paul Matheson waited while Lanyon toweled himself down after the shower and climbed into a clean uniform.

"We're all set to move off, Steve. We've had a last check around the base; there's no one here."

Lanyon nodded. "Fine, Paul. By the way, how's the girl who came aboard with me?"

"Miss Olsen? She's O.K., a little shocked but she'll come to. Looks as if you had quite a job getting back here. She's sharing a cabin with the three WAC nurses. Tight squeeze. We've got about sixty extra passengers."

"Sorry to bring another, Paul. Still, she can have Van Damm's vacancy. If it's any consolation, she's with NBC; she's probably taking all this down in cinemascope. Remember, it's not enough to make history-you've got to arrange for someone to record it for you."

Lanyon buttoned his shirt up, glancing at the movement signal from Tunis lying on the table.

" Portsmouth, England, eh? Do you think they've got any more corpses for us to collect?"

Matheson shook his head. "No, I gather they're top air force and embassy VIP's. May even be the ambassador and his family. Where we'll put them I don't know."

He laughed easily, and Lanyon noticed that Matheson seemed to have filled out considerably over the past few days. There was an air of authority and confidence about him that suggested he had been through his own private ordeal.

Lanyon fingered the movement order. "Paul, this came through three days ago. Strictly speaking, you should have got under way immediately."

Matheson shrugged. "Well, I couldn't leave the skipper behind, could I, Steve?" He hesitated. "As a matter of fact, two more orders came through when we didn't clear back, followed up by a couple of troubleshooters from the Provost Marshal's unit here. Slight problem there. They could see we were all ready to blow, so I had to, er, use a little bit of old-fashioned persuasion."

He grinned at Lanyon, and tapped the butt of the.45 stuck in his belt.

Lanyon nodded. "I wondered what that was for. Thought perhaps you were trying to impress the WAC's. Pretty good, Paul. Well, let's go topside and get this rig under way."

They climbed up into the conning tower, crouched down under the awning stretched across to keep out the spray thrown up off the sides of the pen. At the far end Lanyon could see heavy seas smashing against the open doors, hear the deafening unrelenting roar of the wind screaming past like a dozen express trains.

The entire pen was shifting sideways under the impact of the seas breaking across it, and large cracks split the roof and walls. The _Terrapin_ was moored well back in the pen, double lines of truck tires lashed to her hull to protect her from the pier.

The last lines were cast off, and they began to edge ahead under the big diesels, churning a boiling wake of foam and black water behind the twin screws.

They swung out into the center of the pen, 50 yards from the entrance, bows breaking out of the water as swells rode in from the sea, lifting the sub almost to the roof.

Lanyon was checking the forward elevator trim when Matheson suddenly punched him on the shoulder. He looked up quickly as the helmsman shouted and pointed forward to the entrance.

A huge section of the roof, the full width of the pen and 40 feet across, was tipping slowly downward crushing the two steel gates like chicken wire. Through the wide crack mountainous seas burst like floodwater through a collapsing dam, splashing across the bows of the _Terrapin_.

"Full astern! Full astern!" Lanyon roared into the mouth tube, hanging onto the edge of the well as the diesels reversed and wrenched the sub back into its wake. They moved 50 yards, and then Lanyon held the _Terrapin_ and watched as the collapsing roof section anchored itself in the jaws of the entrance, hanging vertically from the reinforcing roof girders, wedged firmly by the driving seas.

Matheson pounded on the edge of the well, frustration and anger overriding his hysteria. "We're trapped, Steve, for God's sake! We'll never move it!"

Lanyon ignored him, picked up the mouth tube. "Starboard torpedo station! Alert! Charge No. 2 tube with main HE heads."

Waiting for the ready signal, he turned to Matheson. "We'll blast our way out, Paul. That roof section is at least fifteen feet thick, must weigh about five hundred tons. It's our only chance."

At the ready signal he backed the _Terrapin_ astern right up against the rear wall, so that 150 yards of clear water separated them from the entrance. Then, lining the bows carefully on target, he rapped into the tube, "Compressors sealed. Discharge vent open." He paused as the bows swerved slightly, then realigned on the target. "Fire!"

The torpedo burst from its vent in a rush of bubbles, burrowed rapidly through the water three feet below the surface, moving like an enormous shark. Lanyon watched it until it was 20 yards from the blocked entrance, then crouched down, shouting to the others.

They hit the floor, and he seized the mouth tube and yelled, "Full ahead! Full ahead!"

As the screws thrashed and bit in, kicking the _Terrapin_ forward, the torpedo exploded against its target. There was a vivid white flash that filled the pen, followed by a colossal eruption of exploding concrete and water which burst out of its mouth like a cork from a champagne bottle. Simultaneously a 15-foot-high wave swept down the length of the pen, a massive breaker that carried with it a foaming jetsam of concrete and metal. Full ahead, the _Terrapin_ was moving at 15 knots as they met halfway down the pen. It slowed briefly under the impact of the wave, its conning tower glancing off the walls and carrying away a section of the pier. Then it surged forward again, heading smoothly through the gaping mouth of the entrance into the harbor. For a moment its bow rose up steeply under the writhing swells, then sank cleanly into the deep basin, its tower and stern quickly vanishing in a roar of escaping air.