Revealing mistake: It's quite common in movies of the era, especially slashers and horror movies who look to get some particular scenic effect, to feature blood with unrealistic color and look, in particular a bright red. This movie though has some of the worst fake blood ever in both color and texture; when Kopo gets clobbered protecting Shaft it really looks like someone squished a tomato on his head, and when Shaft gets bitten, ketchup-like goop oozes from the actor's teeth.
Revealing mistake: At the end of the movie, the French inspector Cusset (Jacques Marin in his typical role) looks at the mess Shaft made. With a single glance he's able to encompass all the different dead bodies on the large property Shaft covered with his car mowing them down at 60 mph, which already is impressive. Some of the bodies lie down next to each other when they were murdered at distance. Deserving special mention is the second guy Shaft trampled with his car though, with the actor having his hands hidden in the jacket sleeves to suggest that Shaft crushed them under the car tires. (01:50:25)
Revealing mistake: Shaft and Aleme are looking through different castles in a book. Every page starts with the name of a castle, but the book used as basis for the prop is a french textbook by Jean Secret, Le Perigord, which talks about a region (the modern Dordogne, you can read that specific name and many others recognizable as part of that zone when the camera lingers on the page) which is in the south of the country; definitely not featuring a castle "14 kilometers from Paris" as the prop text inlay says nor is a "one castle every other page" tourist guide-style of book. (01:43:20)
Revealing mistake: Flashback to the truck on fire past the Franco-Italian border; the driver chops the lock open, with all the slaves inside banging desperately at the cargo doors to get out of the inferno. Or not; when there's a cut between shots, you can see the lock already came off, but the extras who are supposedly trying with all their might to escape death do in fact wait for the driver to open the door before they start coming out. (00:19:50)
Revealing mistake: When Shaft props the dead guy on the bus against the seat, the blood he drooled on his arm is gone, and as he tries to shut the dead guy's eyelids the not-so-dead actor closes his eyes a second before Richard Roundtree's fingers get to his eyeballs. (00:39:05)
Revealing mistake: Shaft kills two guys who are climbing the stairs out of the catacombs Amafi is holed in. No bullet holes or blood appear on the clothes, and they both use the railings to help their backward tumble down the stairs in a rather noticeable fashion. (01:46:00)
Revealing mistake: In Maiberra, with the big trucks of the villains loudly traversing at top speed the roads, all the women by the road are facing the opposite direction instead, smiling, and some of them looking into the camera. (00:51:10)
Revealing mistake: Richard Roundtree is quite literally butt naked during his stick fight in the Emir's stable towards the beginning of the movie, except in one shot where the person in frame is wearing blue sweatpants. (00:12:50)
