This musical is a lively romp filled with songs and fantasy. In a village of colorful characters, the invisible people exist only in the imagination of the children who invented them.
Cindy's two special invisible friends are a fun-loving pair named Nubbins and Glopp who entertain her with song and dance. When Cindy asks to visit their Invisible Village, the two are skeptical, but agree to take her. There she meets the colorful Invisible Villagers, all invented by children like Cindy.
All is well until General Grumpdump decides he must capture a real person in order to become dictator. Cindy is the unlucky candidate, and must stay in a picket-fence prison while Nubbins and Glopp work to free her. They discover that when an invisible person touches the shoulders of a real person, it changes their character. With nothing to lose, they devise a plan to trick old General Grumpdump into undergoing a character change. The plan works as Cindy is freed and General Grumpdump is transformed into a generous sort.
At summer's end, Cindy realizes she's too old for invisible friends, and bids Nubbins and Glopp goodbye. Luckily, they are quickly re-invented by a younger child in need of some "true and faithful friends" who will be there "through thin and thick!"