In this game, you play Ace, a dashing space hero who must fight the space villain, Bort, who plans to use his special device, the Infanto Ray to conquer the universe by reducing his enemies' age to the point where they are too young to oppose. Unfortunately, that job is complicated by the fact that Ace himself was hit with the ray and now is only a young boy. Regardless, his girlfriend is abducted by the villian and the pursuit must continue. However, there are times when you can choose to have Ace's full vigour of his proper age temporarily restored, but the price of additional danger that rises to match his strength.