The Mechanic Arthur Bishop is a veteran hit man who, owing to his penchant for making his targets deaths seem like accidents, thinks himself an artist. Its made him very rich, but as he hits middle age, hes so depressed and lonely that he takes on one of his victims sons, Steve McKenna, as his apprentice. Arthur puts him through a rigorous training period and brings him on several hits. As Steven improves, Arthur worries that hell discover who killed his father.