Revealing mistake: In a scene where the canoes are shooting the rapids through a sheer cliff you can clearly see a stuntman climbing out of the water onto the rock.
Visible crew/equipment: Near the end of the chainsaw sequence, a crewmember's hand is visible on Krug's back.
Continuity mistake: Watch the bar scene about ten minutes from the start of the film. The barmaid is holding 2 pints, but note how the froth disappears when the shot changes as they are placed on the bar.
Continuity mistake: Several characters say that the train leaves from Shanghai. But the caption at the beginning says that the starting location is Peking (which is in fact where the real Trans-Siberian Express did depart from).
Plot hole: Shaft's friend has been killed at the beginning of the movie. Bad guys show up at his sister's door for a fake flower delivery, and Shaft kills them. He asks the dying baddie "Who put a contract out on me?", but how does he know? We as audience know there is indeed a contract on Shaft since we've seen the conversation with the mobster, but as far as Shaft knows, all evidence points at Arna being the target, and he even explained the money-related motive a mere minute before.
Revealing mistake: At the beginning of the film O-Yuki is fighting the men in the forest and kills them one by one. When she kills the last one there is a close-up shot of her dagger entering his rib area and blood sprays out. However, if you pay close attention you can see the blood sprays out of his sleeve (presumably there is a device in there), not his torso. (00:01:18)