Wool (the book upon which the Silo TV series is based) is an interesting exploration of a path humanity might take to survive self-inflicted extinction. The setting, as you may have guessed, takes place in a big vertical tube that extends deep underground. In this case, the silo is a self-contained habitat designed to protect its for an unspecified amount of time from a world where exposure to the outside atmosphere can kill in seconds.
It begins from the perspective of a widower sheriff whose crimes, which people of today would call negligible, have earned him the death penalty via cleaning duty of the silo's only view to the outside world: a series of lenses linked to video screens inside. Earth has become so caustic that even a brief task such as that is a one-way trip reserved for criminals and those who've lost their sanity and have to get "out."
The book then goes through a series of flashbacks, which I'm not a big fan of, and few perspective changes that made it difficult for me to attach to any particular character through which to learn the world. I set the book down for a while here, and was glad after I eventually picked it up to see it settle on Julie, a stereotypically strong-willed female mechanic living at the bottom of the 100+ story silo, and happy to stay there.
If only she had. Julie is lured into the sheriff's old position and learns the hard way about the circumstances that led to his fatal cleaning duty, and a series of other suspicious deaths within the silo itself.
The story then divides itself between Julie and her unrequited crush, Lucas. Unfortunately, Lucas lacked Julie's charm and drive, making him a hard character to root for, and his chapters difficult for me to finish.
Characters aside, the book paints an interesting picture of humanity forced to live in small confines, and the mechanisms that might be required to ensure peace—or at least stability—over many generations. Howey does a marvelous job describing the different functions, separated by level and depth, as well as the grueling dredge of traversing those levels without an elevator, and why most people avoid it.
That's right: video screens, but no elevator. Computers, but no email. Sound draconian, backward, or unrealistic? Howey explains that, too, so keep reading, if only for the litany of plot curveballs he throws with practiced ease to keep you guessing.
Apart from the flashbacks and dramatic cast change, my biggest issue was simply that I didn't agree with how humanity would react to certain key events in the story. This made it difficult to buy into the world and become invested in the plight of characters whose base motivations I couldn't get behind.
Side note: I don't like to even mention my own books in reviews, but as we all know, every rule has exceptions. Holtondome explores a dome society in a not-quite-as-deadly post-apocalyptic Earth who face a similar situation, but have evolved differently and have very different philosophies and motivations. You might quickly spot where my book and Howey's diverge. Not a criticism, Mr. Howey, just a difference in opinion.
All that said, I'm glad I read the book, and would do so again. The topics are relevant to the problems of today. I'm a big proponent of science fiction serving as an exploration—and warning—about the future. In that capacity, Wool wholeheartedly delivers.