Nuclear fire brought endless night.
The darkness hides invisible terrors known as entities.

After the end of the world, Dr. Swaggart knows a demon has infected mankind's last shelter. He knows of a cure: but that means going down the mountain. In the dark. And with a damaged oxygen tank.

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Sheltered in the underground Ark 1 facility, Earth's last 300 humans fear the dark above all else... the shadows hide an ancient, primal evil—one that can take control of people, and which humans have no defense against. Deep within the miles of well lit corridors, the lights begin to flicker and fail.
Before a new darkness falls, a drug addict and a man with Downs syndrome must reclaim the light and stop a new and final demonic Armageddon... but they learn that someone inside Ark 1 had more to do with unleashing these hellish fiends than any of the survivors know.
Stay in the Light... Stay alive.
Get book 1 in this sci-fi thriller now!