Beleaguered professor Ned Brainard (Fred MacMurray) has already run into a pile of misfortunes with his discovery of the super-elastic substance "Flubber." Now he hopes to have better luck with a gravity-busting derivative he's dubbed "Flubbergas." Ned's experiments, constantly hampered by government obstruction, earn the consternation of his wife, Betsy (Nancy Olson). But a game-winning modification to a football uniform may help Ned make the case for his fantastic new invention.