If everyone was the same it would be a very, very dull world. Life partners Barry and Benny Beetle find two abandoned eggs on the underside of a leaf in Chicago's Millennium Park. To keep them from being eaten by predators, they take the eggs home. The eggs evolve into larvae, then pupae, then adult. Barry and Benny are surprised, to say the least, about the children they must now take care of. And along the way, Barry and Benny meet a new friend: Franky Fly.