The year is 2149, and mankind has yet to spread outside the solar system. There are a few research posts on Mars, but the biggest hub of activity (outside of Earth) is the Stakhanov mine on the dark side of the moon, where a huge crater has been dug to mine valuable Helium-3.
Inside the pitch-dark crater, miners work day and night (not that such times exist on the moon) thanks to new cybernetic implants, reducing the need for sleep down to a luxury instead of a necessity. A central computer, coupled with an artificial intelligence, coordinates the workforce and monitors productivity.
When a solar flare strikes, dousing cosmic radiation across the surface of the moon, everything stops. Some workers collapse on the spot, the overload frying their brains, but those that survive aren't much better off. The flare has corrupted the complex's AI, sending it into a calculating homicidal rage; turning the facility's equipment against them and unleashing a mental assault on the remaining workforce via their implants. The miners find themselves trapped in their own memories, fighting an unseen foe in their heads as they struggle to escape the hostile environment.