Director Yung-tsu Yeh is one of the unknowns of the Shaw studios who deserves more recognition. He had a short career directing before switching over to acting full time. This is one of his earlier films but it shows a steady hand and a good feel for characters unlike many HK films where character development is unnecessary.
The film opens with an attempt on the life of the Royal Eunuch. This fails but the assassin leaves a clue pointing the conspiracy back to the emperor. The eunuch's very presence causes the emperor to quake in his seat and it seems that the royal staff's loyalties are more on the eunuch's side then the emperor. The eunuch uses the attempt on his life as motivation to carry out his plan to kill the entire royal family and replace the emperor with a someone more to the eunuch's liking. The prince is away so the eunuch sends a battalion to kill him. The prince, unaware of his family's demise, prepares to return to the palace but is diverted by a hermit running off with a woman's baby. The noble prince gives chase but becomes lost in the woods. The hermit, woman and baby turn out to be father, daughter, grandchild and the kidnapping was a ruse to rescue the prince from the eunuch's plot. The old man is revealed to be the legendary Old Hermit of the Green Bamboo Forest and he's an invincible pole fighter. Meanwhile the eunuch is visited by a frail old man who turns out to be the eunuch's father. The old man has been looking for his son for 20 years and he tells him that the eunuch is the father of a daughter out of wed lock (conceived before the castration, of course). This news is not something the eunuch wants to hear as this would ruin his reputation so he kills his father and orders his soldiers to kill his daughter and the mother. This plan would have succeeded if not for the intervention of the Old Lady of the Green Bamboo Forest. She rescues the daughter and joins with her husband, the Old Hermit. The two learn from the hermits and prepare for their revenge, with the young girl unaware that the prince is planning to kill her father.
Complicated? Yes, but the film is very snappy and it mostly makes sense. The director, who made the fun "Black Tavern" a year later, has a very solid command of the craft. The fights are well choreographed and keep away from the trampolines and wires until the finale. Unfortunately the wire work is sub-par and that takes away from the finale a bit. The actors are all good especially the woman playing the eunuch's daughter. There are a few scenes of character interaction that really add to the film, the scene between the eunuch and his father or the scenes between the Old Hermit and the Old Lady for example. However there are some silly plot elements that might take away from your enjoyment, the hero keeps forgetting about his special technique, for example.
Enjoyable old school.