Doraemon shows Noby a cape that turns the user into a superhero, but Big G bullies them into giving the cape to him, and uses it to become superhero G-Tastic G, whose only power is being able to fly when summoned by a whistle. Big G soon learns that the superhero life is its own harassed existence, as the cape forces him to perform one hundred tasks before he can take it off and a whistle summons can interrupt whatever he is doing at the time, including eating.