Sheriff Holston wants to go outside—outside of the underground silo system where people migrated after the world became toxic for humans. His wife went outside three years ago, after winning the lottery to become pregnant and failing to do so. Maybe her decision was based on digital records she discovered of the founders’ secret. In any case, Holston prepares himself to go outside the silo.
Howey depicts dystopia in a brutally honest way, exposing the deepest, darkest emotions of humans trapped like the animals they used to place in cages, with pragmatic regulations culminating in inevitable population control methods. Holston’s inner thoughts once he reaches the outside zig and zag, his emotions sliding low and soaring high, based on his observations and conclusions about why the people leaving always clean the cameras that let the people inside observe the devastated world.
There’s no mention in the story of what apocalyptic event sent them underground, or the infrastructure of the silo system, but only hints of hierarchy (mayor, sheriff, etc.) and attempts to limit reproduction through an annual lottery. Perhaps these are addressed in the following books of the series. This first one is free on Amazon for Kindle.