Mistakes
When Robin Williams puts the flubber into his back pocket to show Sara how it will bounce him back up, you can clearly see a hole in which the flubber escapes. When he falls to the ground and Robin Williams turns over the hole is gone. See more...
Movie Mistakes blog
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Flubber (1997) - 1 trivia entry
Directed by Les Mayfield, starring Christopher McDonald, Clancy Brown, Robin Williams, Ted Levine (add more)