Continuity: The egg timer in the jail is about to run out, but when Dale runs over to it and tries to turn it over, there is more sand in it than before.
Mistakes
When Flash is rescuing Barin from falling into the void, he rubs against one of the spikes and it bends as if made of rubber. See more...
Trivia
Max von Sydow's costume for the Emperor Ming weighed over 70 pounds and he could only stand in it for a few minutes at a time. See more...
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Flash Gordon mistakes
Continuity: There are a couple of instances in the movie where the models do not correspond with the actual sets. When Klytus arrives at the Hawkmen city he lands near the top of the city. Yet in that very hall there is a pit with a deep void underneath. Such a room could only exist at the bottom of the city. Also, when the Hawkmen start to land on Ajax, its engine section appears to be missing.
Revealing: When Biro stabs the Imperial soldier with his sword, it's obvious that the sword is angled to miss his body.
Flash Gordon trivia
Max von Sydow's costume for the Emperor Ming weighed over 70 pounds and he could only stand in it for a few minutes at a time.