The story tells of a group of villages, Weedom, all living in harmony with one another and nature. However, according to the legend, every hundred years a group of "armored beasts" emerge from "the dark core of the earth" to serve their master, the Queen Pede, and aid her in the destruction of the Wee people. Every time this happens a magic stick is employed to find a hero to defend them. Every time the insects are defeated, the villagers believe that the threat has permanently ended; but they always return, as the legend indicates.

The player plays as Wally, the chosen hero to fight the insects that century, who is to take control of the shooter, a vehicle made for, as its name indicates, rendering shots against the insect menace. Thus, the player embarks a journey across five worlds: Weedom, Frostonia, Inferium, Enigma, and Evile (each consisting of about 5 levels each, with the final level of each including a boss that must be defeated), in order to end the curse forever.