Ralph Spitzle is a typical nine year old boy, anxiously awaiting summer vacation. Life in a small town provides ample opportunity for biking, goofing and friends, all of which were on the horizon. However, on the night before the start of vacation, an atmospheric event sent an incredibly powerful gaseous orb to Earth that had a remarkable effect on Ralph, and as he will discover, on a mild-mannered restaurant owner. Ralph soon realizes that what most nine year olds find an enjoyable pastime has become an unbridled super power.
Ralph's now-complicated summer becomes a nightmare when the evil Cabbage Roller arrives. The Cabbage Roller creates havoc at the summer carnival, sending the poor folk of Woobegoon running for their lives. This presents Ralph's first great challenge, and he is able to muster enough courage to ward off the Cabbage Roller.
The incredible stress on Ralph - caused by these strange powers that he must keep secret - is alleviated by the return of an old friend - Ronnie Sharp - who helps Ralph realize that with mediocre power comes mediocre responsibility. Emboldened, Ralph sets out to learn to control his new ability and use it to defend the town....