The story is set in China during the Qing dynasty. A pair of precious blades known as the "Mandarin Duck Blades" are being transported to the Forbidden City by a security company commissioned by provincial officials. The blades are highly coveted by many martial artists in the "jianghu" because they are rumoured to hold a secret to invincibility. The officials have also detained the security company chief's family members under the pretext of offering them protection, so as to ensure that he does not keep the blades for himself.