Behind them — or rather, below them — water was flooding up into the cargo bay. It rose quickly through the hold, entering the helicopter via the wide-open loading ramp and any other orifice it could find.
Thankfully, the cockpit was airtight, so at seventy feet down, the still-sinking helicopter reached equilibrium — and an air pocket formed in the upturned cockpit, the same way a drinking cup submerged upside-down in a bathtub will form an air bubble.
The helicopter glided downwards until, at ninety feet, it hit the bottom.
A billowing cloud of silt exploded all around the Super Stallion as its destroyed tail section impacted against the floor of the lake and came to rest — still upright — against a massive submerged boulder.
'We haven't got much time,' Schofield said. 'This air will go bad real fast.'
'What do we do?' Book II said. 'If we stay, we die. If we swim to the surface, we die.'
'There has to be something…' Schofield said, almost to himself.
'What do you mean?'
'There has to be a reason…'
'What are you talking about?' Book II said angrily. 'A reason for what?'
Schofield spun to face him. 'A reason why Botha stopped here. In this spot. He didn't stop here for the hell of it. He had a reason to drop anchor here…'
And then Schofield saw it.
'Oh, you cunning bastard…' he breathed.
He was staring out over Book II's shoulder, out into the murky green haze of the underwater world.
Book II spun, and he saw it, too.
'Oh my God…' he whispered.
There, partially obscured by the aqua-green mist of the water, was a structure — not a boulder or a rock formation, but a distinctly man-made structure — a structure which looked totally out of place in the green underwater world of Lake Powell.
Schofield and Book saw a wide flat awning, a small glass-windowed office, and a wide garage door. And underneath the awning: two old-style petrol pumps.
It was a gas station.
An underwater gas station.
It was nestled up against the base of the cliff, at the point where the enormous circular crater containing the small mesa met a wide canyon stretching westward, right on the corner.
It was then that Schofield remembered what this gas station was.
It was the rest-stop petrol station that had been flooded over when Lake Powell had been created in 1963 by the damming of the Colorado River — the old 1950's-era gas station that had been built on the site of an old trading post.
'Let's move,' he said. 'Before we use up all the oxygen in here.'
'To where?' Book II asked incredulously. 'The gas station?'
'Yep,' Schofield said, looking at his watch.
It was 9:26.
Thirty-four minutes to get the Football back to the President.
'Gas stations have air pumps,' he said, 'for inflating tires. Air that we can breathe until those Penetrators go away. Maybe when the government compensated him, the guy who owned this station just upped and left everything behind.'
'That's your magic escape plan? Any air left in those pumps will be forty years old. It could be rancid, or contaminated by God-only-knows what.'
'If it's air-sealed,' Schofield said, 'then some of it may still be good. And right now, we don't have any other options. I'll go first. If I find a hose, I'll signal you to come over.'
'And if you don't?'
Schofield unclipped the Football from his webbing and handed it to Book II. 'Then you'll have to come up with a magic plan of your own.'
The Super Stallion lay on the bottom of the lake, surrounded by the silent underwater world.
Abruptly, a finger of bubbles issued out from its open rear section — trailing the figure of Shane Schofield, still dressed in his black 7th Squadron battle uniform, as he entered the water from within the sunken helicopter.
Schofield hovered in the void for a moment, looked about himself, saw the gas station, but then suddenly he saw something else.
Something resting on the lakebed directly beneath him about three feet away.
It was a small silver Samsonite container — heavy duty obviously designed to protect its contents from strong impacts; about the size of two videocassettes placed side by side. It sat on the silty lake floor, perfectly still, weighed down by a small anchor.
It was the object Gunther Botha had tossed over the side of his bipod when Schofield and Book had interrupted him.
Schofield swam down to it, cut away the anchor with a knife, and then attached the silver container's handle to the clip on his combat webbing.
He'd look at its contents later.
Right now he had other things to do.
He headed for the underwater gas station, pulling himself through the water with long powerful strokes. He covered the distance between the Super Stallion and the gas station quickly, and soon found himself hovering in front of the ghostlike submerged structure.
His lungs began to ache. He had to find an air hose soon…
There.
Beside the open doorway of the gas station's office.
A black hose, connected to a large pressurized drum.
Schofield swam for it.
He came to the hose, grabbed it and pressed down on its release valve.
The hose's nozzle sputtered to life, spewing out some pathetically small bubbles.
Not a good sign, Schofield thought.
And then, in a sudden billowing rush, a wash of big fat bubbles came bursting out of the hose.
Schofield quickly put his mouth over it and, without a second thought, breathed in the forty year-old air.
At first, he gagged, and coughed awfully. It tasted bitter and stale, foul. But then it got cleaner and he began to breathe it in normally. The air was okay — just.
He waved to Book in the helicopter, gave him the thumbs-up.
As Book swam over with the Football, Schofield pulled the air hose into the gas station's little office, so that any stray bubbles got trapped against the office's ceiling rather than rising to the lake's surface and alerting the Penetrators to their new air source.
While he did so, he looked at the submerged gas station all around him.
He was still thinking about Botha.
The South African scientist's escape plan couldn't have involved just coming to this sunken petrol station. It had to be something more than that…
Schofield looked around the gas station's office and the garage adjoining it. The whole structure was nestled up against the base of the sunken cliff.
Just then, however, through the rear window of the little office, Schofield saw something built into the base of the cliff behind the gas station.
A wide boarded-up doorway.
It was constructed of thick wooden beams, and it appeared to burrow into the cliff face. A pair of mine-car tracks disappeared underneath the planks that sealed its entrance.
A mine.
Botha's plan was beginning to make more sense.
Thirty seconds later, Book II joined him inside the office and gulped in some air from the hose.
Another minute and Schofield leaned outside the office and saw the blurred rippling outlines of the Air Force Penetrators above the surface wheel around in the air and depart heading back for Area 7.
