Wu Chun , Han Geng, Barbie Hsu (Tsui Hei Woon) starred MY KINGDOM had a fight scene between Wu Chun and Han Geng. Under Big Brother Sammo Hung Kam Bo's instructions they fought like they were "counterfeit Donnie Yen Chi Tan".
Hung Kam Bo gave hands on instructions to Han Geng and Wu Chun and even personally demonstrated the fight moves. He also demonstrated all the expressions that went along with the action, like training Yen Chi Tan he instructed the martial art new comers. Reportedly the fight scene took over 50 hours to shoot. Because this scene was rather dangerous, Big Brother and the stunt team repeatedly rehearsed a dozen or so times before permitting Wu Chun to personally perform.
After Big Brother's hellish training and Sammo Hung stuntman association's 24 hour personal training, Wu Chun and Han Geng before the action scene already sparred and rehearsed to memorize their moves. In the film Han Geng with a dagger in hand had to remember the moves and steps as well as avoiding injuring himself and Wu Chun. Wu Chun had to put on wires. When Han Geng kicked him down the stairs they needed coordination to be able to complete. Wu Chun and Han Geng were on the wires for two days, shoulders and arms due to long time fighting were covered in bruises and scars. Yet their professionalism touched Big Brother a lot.
Source : hongkongmorning.com