Nine-year-old Oscar often gets picked on for his small size, but he's a little boy hiding a big secret: he's Nanoboy, the world's tiniest superhero. When there's trouble in the world of molecules, Oscar shrinks down to be smaller than the average cell to fight off little villains that could mean big trouble. While dealing with these microscopic dangers, Oscar still has to live the life of a regular kid, complete with homework and peer pressure, and often uses what he learns fighting evil to help him solve problems in the human world.