Bearmouth by Liz Hyder

Life in Bearmouth is one of hard labour, the sunlit world above the mine a distant memory. Reward will come in the next life with the benevolence of the Mayker. New accepts everything - that is, until the mysterious Devlin arrives.

Suddenly, Newt starts to look at Bearmouth with a fresh perspective, questioning the system, and setting in motion a chain of events that could destroy their entire world. In this powerful and brilliantly original debut novel, friendship creates strength, courage is hard-won and hope is the path to freedom.