Revealing mistake: When Itto puts the cover on the baby carriage it's obvious that the sudden downpour of rain is just a sprinkler placed in front of the camera. Pay attention to the cover, Itto's clothing and the puddle behind the carriage, they remain completely dry/untouched. (00:11:00)
Revealing mistake: The protagonist jumps from a bridge and boards the train to try to save the Professor. When he is walking on the top of the carriages, look at the treetops in the background; the train is stationary. (00:12:00)
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.
Revealing mistake: When Anguirus makes his sacrificial charge against Gigan, the hand that is moving the Anguirus costume can be seen holding it.
Revealing mistake: During the iconic dojo brawl scene, Bruce Lee at one point picks up two men and whirls them around. It's obvious in the wide shot that they are just dummies.
Revealing mistake: When Itto is bathing, near the beginning of the film, he hears the clanking sound and then there is a close-up shot of his face. The start of his wig, the hairline, is visible. (00:08:48)