When a train travelling across the United States carrying the newly appointed Japanese Imperial Ambassador is robbed by "Gauche" (Alain Delon) and his gang, they steal a samurai sword that is to be a gift from the Meiji to President Grant. It now falls to the perfectly attired warrior "Jubei" (Toshirô Mifune) to retrieve the weapon and luckily, they have one member of the gang who was accidentally left behind - "Link" (Charles Bronson) - to help. Gradually, the two men (and their cultures) begin to bond and it is soon clear that both men have a grudge against "Gauche". This beef leads them…