Invincible Armor is a 1977 Hong Kong-Taiwanese kung fu film starring Hwang Jang-lee, John Liu, and Tino Wong.
On patrol through town, Ming General Chow (Liu) observes a fighter, Hu Lung, fending off a group of bandits.
Impressed by the fighter's skills, General Chow arranges for Hu Lung to meet the Minister of Royal Security as a potential candidate for joining the Ming forces.
Ming Minister of State Cheng (Lee), an authoritarian ruler and master of the Eagle Claw and Iron Armor techniques, summons his most skilled enforcer, Shen Yu (Wong), to hunt down Chow and arrest him.
That night, when staying at an inn nearby, multiple assassins attack Shen Yu, but he is saved by an unknown individual who also delivers him a strange letter.