Greatfall: A Silo Story (Part 3) is the final installment of a dark new story set in the world of Wool, Hugh Howey's post-apocalyptic vision of humanity and its struggle to survive. In Part 3, the longest installment of the series, Silo 23 is darker than ever before. While Maya and Esther flee into the down deep, Matthew subjects Isaac to the sort of rigorous conditioning that robs the boy of his soul. Daniel wrestles with his new identity, tormented by what he has learned. And the believers, just pawns in a centuries-long game, begin to learn the truth... In this pounding conclusion to Greatfall, thousands of people confront their nightmares. Not all of them will survive, but those who do will have one hell of a story.