When Campbell and Cole are inside the Chinese herbal-like shop, the woman behind the counter offers Campbell a drink. When he goes to drink it he holds the cup with two hands but in the following shot he's holding it with only his right hand.
Steven Seagal had some sort-of religious "breakthrough" before filming began and decided he didn't want to kill any villains in the movie. This caused some friction on the first day, when he was set to film a scene where he killed Stephen Tobolowsky. Tobolowsky, knowing how spiritual Seagal was, ended up convincing Seagal that killing his character was the right thing to do, as it would allow his character to be redeemed and reborn in a new body through reincarnation. The scene was filmed as it was scripted. Later, however, Tobolowsky got a call from the director, who informed him that Seagal kept improvising lines implying that Tobolowsky survived. Tobolowsky ended up having to come back out and record some wonky dialog of his character screaming "Finish me off!" to imply he survived and appease Seagal. In the end, the lines weren't used and Seagal's improvisations were simply cut out, so Tobolowsky is killed off as was originally planned.