From her hips down to her ankles, the black rubber suit was beaded with drops of water which slid further down with every muscle she moved. "For ten minutes at least," Kuryakin said, "we'd be leaving wet footprints everywhere. And since our only card to play is surprise, I think we'd better not take the chance."

Coralie nodded, frowning slightly. They stripped off the underwater suits and dropped them in two damply quivering heaps beside the aqualungs. Kuryakin was wearing his favorite jeans with a black turtleneck sweater; the girl, also in black, was in a stretch-nylon cat suit.

"I guess we'd just better leave everything here," Illya said. "They're hidden from all but the closest inspection by these drums - and the midget's out of sight around the stern of this nuclear monster."

From a waterproof satchel attached to his aqualung, the agent produced his Walther, the girl's Berretta, and one or two specialist devices which he stowed in his jeans. Then, moving swiftly but on tiptoe, they strode towards the double doors at the far end of the quay. "This is the part, most of all, where you need to keep your fingers crossed," Illya said. "If there's no way of opening these except by some master switch inside, we're –" He paused in mid-sentence. As they passed into the embrasure housing the exit from the chamber, the first pair of doors swung open before them with a muffled hiss of compressed air.

"Magic-eye beam," he commented. "They must have an automatic cut-out overriding it once the control to flood the chamber has been actuated - otherwise the lake water would break the beam and the doors would open to let it in and inundate the whole place!"

They walked into the air-lock, waited until the padded doors had swung closed, obeyed the illuminated notice saying in five languages: IMPORTANT! DO NOT ATTEMPT TO OPERATE HANDLE OPENING SECOND PAIR OF DOORS UNTIL RED BULB HAS STOPPED FLASHING! - and then operated the handle.

Beyond the inner doors as they swept apart a short length of empty passage stretched. It terminated in a T-junction with a wall plaque direction indicator.

Kuryakin and the girl flitted soundlessly up. Flattening himself against the wall, the agent listened. On the threshold of hearing, machinery hummed somewhere; louder - although still not very near - a confused murmur of voices surged. In the immediate neighborhood, all seemed silent.

He peered cautiously around the corner.

The two arms of the passage curved symmetrically away from him - as though they were circling some central feature, perhaps a giant shaft - each one boasting a collection of doors on its outer wall which began about forty feet beyond the corner. To the left, the indicators read: BRIEFING… OPERATIONS CONTROL… COMMUNICATIONS… WELFARE… LIBRARY. Those pointing to the right were labeled: MAINTENANCE… ARMORY… CATERING… PERSONNEL… ELEVATORS TO B, C, ADMINISTRATION AND REACTOR. There was nobody in sight along either arm.

"Right looks more interesting," Illya murmured, "but it's where those voices are coming from - and there's about a hundred and twenty crew members of that sub to account for, besides Heaven knows how many members of their private army. We'll play it safe and take the left!"

With their guns ready, they stole noiselessly into the fortress.

Chapter 12

Hearse Under Water

THE SECOND DOOR on the left of the curving passage stood ajar. Through it, Illya and Coralie Simone could see a fair-sized room equipped with a blackboard and benches rather like a school classroom. In the corner nearest the corridor a large desk littered with papers stood by a green baize board carrying charts and graphs and schedules. The door of the room, which was empty, bore a small plaque on which was engraved the word BRIEFING.

"This must be where the leaders come to get their orders before they set out on their various missions…" Kuryakin began. He stopped. Approaching around the curve of the passage, voices distantly echoed.

Seizing the girl's arm, he thrust her through the half-open doorway. "Let's hope whoever it is isn't on his way to a briefing, anyway!" he whispered as he thumbed back the safety catch on his gun. He pushed the door almost shut, and peered through the crack as two officers in khaki and black uniforms passed down the passage and continued on around the bend conversing animatedly in a language Coralie could not place. "Serbo Croatian," the Russian murmured with a jerk of his head in the direction they had taken. "They were on their way to the canteen. Let's hope the majority of Thrush's personnel are there… it's at least the right time for dinner, so maybe we'll be in luck."

Coralie had found among the wall charts behind the desk what appeared to be an exploded diagram of the fortress, showing the relationship of the levels one above the other. "We'll try and memorize it," Illya murmured. "It might save us a lot of time… or possibly even our lives."

The basic design of the place could have been represented by three oval pans one above the other, the topmost pan having a short handle - which represented the submarine pen. There seemed, as Illya had surmised, to be a column of rock standing away from the valley wall on which this projection was supported, the remainder of the fortress fitting in between wall and column.

The circular passageway to which the corridor from the pen led was repeated on all three floors of the fortress. On its outer periphery it admitted, on the floor they were on, to a communications complex, to welfare and library sections, to the canteen and to the personnel branch; on the middle floor to living quarters, offices, an armory, the radio room and more catering facilities; and on the lowest level to stores, a cell block and more offices. Within the area circumscribed by the passageway, the bottom floor housed the reactor and the next a circular council chamber which was two stories high and rose to the top floor. From here - on the opposite side of the passage they were traversing - a door appeared to lead to a gallery circling the chamber and some kind of control center at one end of it.

"What I didn't realize," Illya said, "was that they have, of course, this great maintenance unit. Look, we'd have passed it if we had chosen the other branch of the passage. It seems to connect with the pen - I guess there must be sliding doors we didn't notice on the side opposite the quay. After all, even if they didn't actually make the sub here and shipped the bits in by air and truck, it had to be assembled here and that needs quite an advanced shop."

"Yes," the girl said. "And here's where it came in - look, at one side of the reactor on the lowest floor: it's marked Truck park, and there's an arrow pointing to where it says Double steel doors. What d'you bet those doors blank off the tunnel leading to the estancia?"

"No takers," the agent grinned. "What I want to find out is how they operate! First of all, though, let's see if we can locate Napoleon… If there's a cell block, he's probably in it."

At the opposite side of the fortress from the corridor leading to the pen, there was apparently a bank of elevators and some stairs. "We'll go down those," he said. "They're probably only used for emergency... and this is an emergency, anyway!"

Cautiously, they eased open the door and crept out into the passageway. There wasn't a soul in sight. Nor did they see anybody as they sped past the closed doors and gained the open space where the elevators were. Voices were approaching, however, from the direction of the canteen down the other arm of the corridor. Swiftly, the agent pulled the girl after him down the concrete stairway which twisted away around the shaft housing the three elevators.