Bumbling professor Ned Brainard accidentally invents flying rubber, or "Flubber", an incredible material that gains energy every time it strikes a hard surface. It allows for the invention of shoes that can allow jumps of amazing heights and enables a modified Model-T to fly. Unfortunately, no one is interested in the material except for Alonzo Hawk, a corrupt businessman who wants to steal the material for himself.
When Billy Peltzer is given a strange but adorable pet named Gizmo for Christmas, he inadvertently breaks the three important rules of caring for a Mogwai, and unleashes a horde of mischievous gremlins on a small town.
Samantha's life is going downhill fast. She has a crush on the most popular boy in school, but the geekiest boy in school has a crush on her. Her sister's getting married, and with all the excitement the rest of her family forgets her sixteenth birthday!