No one who enters Ching's castle ever leaves. Enslaved and forced to work in the castle's secret gold mine, the workers endure a daily cycle of brutal punishment. Kang, one of the workers, finally decides to fight back against the oppressive master Ching, but his first attempt at rebellion fails. As a consequence, Ching has Kang’s hands broken to deter others. However, Kang’s resolve to destroy the castle and its master only strengthens. With only one hand remaining, he seeks to learn the 'Heaven Legs' technique, preparing for a final, deadly confrontation with Ching.