Actor Li Dongxue (left) and Peter Ho will star in Brother. Photo provided to chinadaily.com.cn

Liu says the movie, which took five years to prepare, has used the same green-screen technology as the 2005 Hollywood action thriller Sin City.

The cast members, including Chinese-American star Peter Ho and up-and-coming star Li Dongxue, has to perform in an 800-square-meter, discarded factory-turned studio, with all of its shooting rooms packed with floor-to-ceiling green screens.

"It had been tough at the beginning, as the actors have to perform in a void. After much practice and updating our computer technology, I believe the movie has reached the best effect," says Liu.

Brothers will be released on the Chinese mainland on Aug 14.