Mitch has a potassium deficiency, so his Aunt Diane and mother, Patti, have to return to give him his medicine. Later, Mitch, his sister, Jenny, and their cousin, Adam, return home and discover that their parents are not around. After they hear an old message on the answering machine, they believe their fathers are at a space shuttle launch. Later, when Jenny decides to throw a party, her friends arrive, including her friend, Jill, whose heart Mitch and Adam desperately try to win.
When Mitch goes to the kitchen, he sees Patti and faints because he needs potassium in his system, to stay awake. Adam, having heard from his father Wayne that bananas have potassium, feeds one to Mitch. The kids soon discover Gordon on the left speaker of the stereo. With Wayne's instructions, they are able to activate the machine, which returns their parents to their normal size.