Revealing mistake: When Weasel says, "How's your back, baby?" to Phyllis, she spits in his face, but Weasel closes his eyes before she spits.
Revealing mistake: When Hattie Jacques and Barbara Windsor see Madeline Smith about her baby, you can see that the 'baby' is an obvious doll.
Revealing mistake: When Shaft fights the bad guys disguised as flower delivery men, both die with their blood packs that explode triggered by visible pyrotechnics - kinda odd to shoot a guy and see literally flames burst out from his chest or back before any blood comes out. (00:48:50)
Revealing mistake: At the beginning, when the woman in the flotation seat is paddling backwards, you can see a fishing line attached to the back of seat that is being pulled to help her move backwards.