In 1880s Wyoming, recently orphaned Lucas Hollister accidentally kills a rancher and is sentenced to hang. In a twist of fate, his estranged grandfather, the notorious outlaw Harland Rust, breaks him out of jail and takes him on the run toward Mexico. As they flee across the unforgiving wilderness, the fugitive pair must outrun the determined U.S. Marshal Wood Helm and a ruthless bounty hunter named Preacher.