Du bi dao da zhan du bi dao (1977)

The madman of martial arts movies (Jimmy Wang Yu) loses an arm, as he is wont to do, and fights the grandmaster of martial arts movies (Lau Kar-Wing), hence the two one arm guys in the title. It starts with manic music and fight sequences. Then a bunch of fighters discuss the old Ching-Ming problem but agree Jimmy is their guy. Cut to a twist on the standard rescue the girl from rape scene in that Jimmy is set up and cuts off his arm to stop the poison from killing him. Jimmy declares he will find the person behind all this. The Grandmaster steps in and explains he is also on a mission for revenge. There is a lot more talk at a grave. It seems everyone is intent on explaining what is going on. Grandmaster has an extended flashback showing why he is looking for revenge and his missing little brother. I can imagine one day Jimmy and Grandmaster were sitting around and Grandmaster said, "I can do that one arm stuff better than you, we should make a movie." So they did. However, I don't think the Grandmaster thought it through. Two one arm guys fighting with swords are actually fencers. Fencing with a foil is different than martial arts sword fighting with broad blade. There is so much more that could have been done in their fight but wasn't. Overall the fights were excellent but the story was not paced well and dragged so I rate only only a notch above average.