The children's series "Captain Underpants" has surprisingly topped the list of the most banned books in America in 2012, beating out the much more controversial title "Fifty Shades of Grey."

The 10-part series, by author Dav Pilkey, follows two prank-loving young boys who create a superhero called Captain Underpants.

Parents say in complaints filed to the Office for Intellectual Freedom that the illustrated books contain "offensive language" that is unsuited to the series' target age group of elementary-school children.

The first book in the series even comes with a "Sturgeon General's Warning" that says: "Some material in this book may be considered offensive by people who don't wear underwear."

So where's the evidence that the books are actually a bad influence on children?

We've broken down the most "offensive" parts of the first "Captain Underpants" book in an attempt to understand why the series is the most banned in the country.

"Offensive Language"

In Chapter 4, the two protagonists of the series — George Beard and Harold Hutchins — refer to their school principal as "that old guy" and call him "Mean Old Mr. Krupp."

Throughout the book, there is reference to undergarments.

Partial Nudity

The hero of the series, Captain Underpants, flies around in underwear and a cape throughout the illustrated book.

In Chapter 17, Captain Underpants slings his underwear at the evil Dr. Diaper in an attempt to defeat him and then covers himself with a barrel. (Note: there is no actual nudity in the book, unless you count Captain Underpants' chest.)

Violence

In Chapter 16 — titled "The Extremely Graphic Violence Chapter" — George and Harold save each other from evil robots by whacking (and presumably killing) them with what appear to be wooden planks.

The chapter comes with the following disclaimer: "WARNING: The following chapter contains graphic scenes showing two boys beating the tar out of a couple of robots. If you have high blood pressure, or if you faint at the sight of motor oil, we strongly urge you to take better care of yourself and stop being such a baby."

Misbehavior

The book is riddled with examples of George and Harold misbehaving. They play several pranks at school, including sprinkling pepper in the cheerleaders' pom-poms and putting bubble bath in the marching band's instruments.

Blackmail/Threats

The principal, who is later hypnotized by George and Harold into becoming Captain Underpants, blackmails the two mischievous students into behaving well at school and doing chores for him by threatening to release a tape of them pranking the football team.

This could be construed as bullying.

***

But what's even more shocking to us than the contents of the Captain Underpants series is why parents are so opposed to a book that gets young boys excited about reading.