Eccentric billionaire, convinced that nuclear war is imminent, lures his family and workers into a luxury subterranean bunker. But when his engineers tapped an ancient aquifer, they released salamander-like predators from 280 million years ago that hunt them through a maze of blind alleys and dead ends as they bolt for the surface.

SYNOPSIS:

American high-tech multi-billionaire Craig McHenry has bought former cold war underground bunkers, planning to turn them into "Noah's Arks" for billionaires in case of global catastrophe.

McHenry now believes he has intelligence that nuclear war is imminent. He takes his wife ELLIE, his two lively daughters MELISSA, 22, and ANNIE, 18, and a team of professionals to ground in the super-shelter IMPERVOS ONE where residents can live for more than a decade with every amenity. Multi-redundant generators supply power. The bunker is biologically self-sustaining, with a state-of-the-art infirmary etc.

OPEN ON UNDERGROUND TUNNEL CONTROL CENTER:

Chief engineer Lance WRIGHT, 28, and two others designed a system that delivers unlimited water from a Mesozoic era aquifer. After tense moments, a fountain of pure water bubbles up. The engineers throw their hardhats in the air, plunge their faces into the water and drink.

Later, they leave to collect their paychecks and return to the upper world. They think Craig is crazy, but they'll take his money.

CLOSE ON a drop of water: Something seems to be wriggling in it. As the engineers leave, a TINY COLORLESS LIFE FORM follows them into the main bunker.

The engineers are angry: Craig refuses to release them. During an initiation ceremony that night, he explains that he chose them to survive the coming nuclear ruin and begin a new civilization. When Lance drunkenly challenges him, Craig has him incarcerated.

Melissa sneaks down to be with Lance as romance blossoms.

Meanwhile, the CREATURES locate the food supplies, gorge and grow quickly.

TIME PASSING

Melissa, opens the door of her bedroom and hears scratching at a closed hallway door. A MONSTER confronts her with an arsenal of teeth. Melissa screams, slams the door and flees.

Lance and the engineers make their way through the underground tunnel to the control room. The creatures have chewed through the elevator and power systems.

When they open the passage to the tunnel, they confront a monster. After an gruesome fight, it sucks down an engineer.

Lance realizes that the aquifer contained creatures from the super-continent Pangaea. During the Permian Extinction, they took refuge underground and evolved to survive while 90% of earth's biota went extinct. They are shockingly intelligent and at home in the moist subterranean environment.

Craig McHenry gathers his family and workers in a "keep" as a last refuge against breach. He arms and organizes a hunting expedition, leaving Lance to extract his family if he doesn't return.

The hunters descend into the tunnel and stalk the CREATURES with weapons and flame throwers. Craig is wounded and orders Lance to make for the exit, as his team sacrifice themselves to lure the CREATURES away.

Lance and Melissa now must get everyone out and seal off the bunker. Hotly pursued by the creatures, Lance and Melissa lead survivors through the twists and turns of the underground tunnel.

They reach the entrance and enter the exit code just ahead of the slithering monsters. But the massive door opens to nuclear chaos: Craig had been right. The world is at war. Military transports pass. The atmosphere catches fire as mushroom clouds and shock waves erupt.

Now the group must decide: try to survive the nuclear holocaust or return to the bunker and fight for their lives as early Man did against predators. As TITLES RUN, the humans re-enter IMPERVOS to battle the creatures and survive until earth is habitable again --- if ever.

IMPERVOS