In their spare time, George and Harold write comic books about a superhero they made up which they called Captain Underpants, hence the name. This character is named after his clothing habit to wear only a red cape and a pair of white briefs. The event that starts it all off is when George and Harold hypnotize Mr. Krupp to act like Captain Underpants whenever somebody snaps their fingers, and then turn back if water is poured over his head.
Here is a list of book titles in the series:
In this episode of Captain Underpants, by Dav Pilkey, George and Harold get into mischief (as they normally do) by screwing up a football game. The principal Mr. Krupp gets so mad at them that he makes them do all of his chores and fix up his house in ways that he wouldn't even bother to do. So George and Harold buy a hypno ring and hypnotize Mr. Krupp to make him act like Captain Underpants, the hero of our story, who runs away from them to fight crime. They (Captain Underpants, George and Harold) stop a bank robber, but then get hit by a truck and are stuck on the truck. When the truck stops moving, Captain Underpants is flung over the truck and hits the wall. Then two androids get out of the truck and go inside. Then they meet the evil Dr. Diaper, who takes Captain Underpants hostage. Inside is a horrible looking machine called the Laser-Matic 2000. Dr. Diaper plans to destroy the world with it. Then, the evil Dr. Diaper hears a plop and goes to change his diaper. During that time, George and Harold destroys the Laser-Matic and unties Captain Underpants. Afterwards, Dr. Diaper comes out of the bathroom, right when George is pulling the self-destruct lever. Then, Captain Underpants shoots his underwear at Dr. Diaper and runs away with George and Harold.
On the cover of this book, it claims to have "Action, Thrills, and Laffs". The Adventures of Captain Underpants