Horton the Elephant hears a small groan from a speck of dust. Believing that an entire society of microscopic creatures is living on that speck, he chases after it before putting it on a flower. Horton discovers that the grain of dust is home to the city of Whoville and its inhabitants are the Whos. Horton begins to bring the flower with him and so the city of Whoville begins to experience strange phenomena, earthquakes and weather changes ;)