Wool

 Wool by Hugh Howey (2011) 528 Pages

I watched "Silo" on Apple Tv, which is based on the first half-ish of this book. I was blown away by the production of the show, we blew through it in a week. I just as quickly devoured this book! If you like thrillers, dystopian novels, post-apocalyptic-esque...etc...this is for you! Really well written. There are a number of differences between the book and the show, I recommend watching the show first. 

Thousands of people live in a sequestered community inside a massive silo underground. The organization consists of the up-top (higher class people like sheriff, the mayor, etc), the mids (middle class jobs and systems such as doctors, farms etc), and the down deep. There are no elevators, and each floor is traversed by a Grand Staircase, a spiral staircase within the middle of the silo. The Down Deep consists of mechanical  and the trash separators. All the people know is that the silo has always been there, it may have been created by a god. The history before 140 years was destroyed by a previous uprising, so nobody knows the history of people or why they are in the silo in general. The outside world is desolate and poisonous, and the only way to "get out" is to request to do so, a grave sin and highest crime in the society. The people follow "The Pact", a set of doctrines written by their predecessors. When someone commits a grave crime, or they request to "go out" they are sent out to "clean". Cleaning means the wiping of the sensor lens which gives the people inside a view of the outside world. There is a hill surrounding the land above the silo, and the people who go out to "clean" always end up wiping the lens. However, the air is so toxic that every single person who goes out to clean will eventually succumb to the toxicity of the outside air. There are numerous bodies within view of the sensor, never to move again or change. 

Because there are ideas and various ways of thinking that are forbidden, a conspiracy is born among various people within the community. Throughout the book we uncover the various lies between the "higher-ups", who have sworn to keep the community safe from creative thinking at all costs. Why are they there? Who put them there? Can they really not survive outside? are various questions some characters attempt to get to the bottom of.