Astronauts have to go down in a cave to shield from radiation

On the last day of the first manned mission to Mars, a crew member of Tantalus Base believes he has made an astounding discovery – fossilized evidence of bacterial life. Unwilling to let the relief crew claim all the glory, he disobeys orders to pack up and goes out on an unauthorized expedition to collect further samples. But a routine excavation turns to disaster when the porous ground collapses and he falls into a deep crevice. His devastated colleagues attempt to recover his body. However, when another vanishes, they start to suspect that the life-form they have discovered is not without danger.

Earth's ozone layer has finally disintegrated, flooding the planet with deadly radiation and forcing all of humanity into underground Radial Shelters. Completely self-contained, these safe-havens allow for the continuation of human kind. When the power supply of Radial Shelter #1364 fails, Isaiah and Jacob must save their community by ascending to desolate terrain. They must venture to the Surface.

Our planet was contaminated by many nuclear explosions that left the soil and the air filled with radiation, and now the few survivors of those catastrophic events live under the ground on a shelter controlled by scientists. After an incident inside the shelter, a group of rebellious scientists defy their leadership when they find a good possibility of returning to the surface.