In the foothills of the Appalachian Mountains, a young coal miner toils a mile underground. Despite the harsh working conditions, Lucas Chaffin takes fierce pride in doing the job once done by the man he loves more than anything, his father. Lucas' father, nicknamed "Bonecrusher," was a strong, handsome man. Now he's withered and sick; coal dust has ravaged his lungs. As life slips away, his greatest concern isn't for himself; it is for Lucas' safety. Bonecrusher is an intimate and moving account of the love between a father and son and the powerful bond they share, a bond that is put to the test.