Hugo is a red, seven-feet-tall, not-so-ordinary helium balloon. His home is the festival grounds where he's tethered to the ground with a long line. He often dreams of sailing high in the sky, completely unattached to anything. One day, he gets that chance when a balloon handler makes a mistake, and Hugo is flying freely in the sky.
As Hugo floats, he encounters a number of things, some that are scary and some that make him happy. He experiences a thunderstorm, meets birds and butterflies, has a near miss with an airplane, gets a picturesque view of the mountains and cornfields, and more.
With a little help from the wind, Hugo the red balloon has a chance to journey across the land and see what there is to see. But he sure is glad when he returns home to the safety and comfort of the festival grounds.