Hong Kong superstar and director Sammo Kam-Bo Hung served as the film's 2nd unit director. The release print of "Knock Off" suffers from the removal of a lot of the martial arts action shot for the film, with a couple of sequences being very heavily edited. The final battle between Jean-Claude Van Damme's character and Australian actor/stuntman Michael Miller is less than half of the action shot for their fight, and upon careful viewing you can pick up the fact that the fight has raged across several different sections on the boat, while the fight between Jeff Wolfe's character Scar and Jean-Claude's is the most heavily edited with more of the action being shown in the "Making Of" featured on several of the DVD editions than in the finished film.
A lot of quality fight choreography by Sammo Kam-Bo Hung was cut from the films final release. This included the drastic shortening of both Jeff Wolfe and Michael Miller's fights against Jean-Claude Van Damme in the finale. In the UK DVD Making Of, a glimpse of Jeff Wolfe's extended fight can be seen.
Jet Li was supposed to play the role of "Inspector Han" but he turned it down last minute to do Lethal Weapon 4 (1998) instead.
The film is one of the last in the world to feature Kai Tak Airport still in use; the airport closed in 1998.