[2] This book tells the story of Horton the Elephant and his adventures saving Whoville, a tiny planet located on a speck of dust, from the animals who mock him.

These animals attempt to steal and burn the speck of dust, so Horton goes to great lengths to save Whoville from being incinerated.

[8] The book tells the story of Horton the Elephant, who, "On the 15th of May, in The Jungle of Nool", while splashing in a pool, hears a speck of dust talking to him.

Horton surmises that a small person lives on the speck and places it on the top of a red clover, vowing to protect it.

In his mission to protect the speck, Horton is ridiculed and harassed by the other animals in the jungle for it since they believe that anything that can't be seen or heard is nonexistent.

The splash they make as they jump into the pool almost reaches the speck, so Horton decides to find somewhere safer for it.

But the news of his odd new behavior spreads quickly, and he is soon harassed by the Wickersham Brothers, a group of monkeys (which are actually apes).

However, the Mayor informs him that Whoville, the town on the speck, is in bad shape from the fall, and Horton discovers that the sour kangaroo and the Wickersham Brothers (along with their extended family) have caught up to him.

So the Mayor searches Whoville until he finds a very small shirker named JoJo, who is playing with a yo-yo instead of making noise.

Dr. Seuss has sold hundreds of millions of copies in over thirty languages of his well-known children's books, which includes Horton Hears a Who!

A 2002 news article in the Santa Fe Reporter details comedic performer Susan Jayne Weiss saying, "Horton is the ultimate metaphor for believing in yourself, your mission and what you know to be true, against societal prescriptions to the contrary".

Additionally, Witherington commended Dr. Seuss for his disdain for cynicism while proving that the imagination can solve life's troubles.

[14] Peter Tonguette, writing for National Review, lauded the book's intricate and thoughtful rhymes and appealing illustrations defined Seuss's work.

This interpretation has been criticized by Audrey Geisel, the widow of the author, and Karl ZoBell, an attorney for Dr. Seuss Enterprises.

It was directed by Chuck Jones, produced by Theodor Geisel (Dr. Seuss), and narrated by Hans Conried, who also voiced Horton.

The cast includes Jim Carrey, Steve Carell, Carol Burnett, Will Arnett, and Amy Poehler.