The story centers on a circular animal-like creature that is missing a wedge-shaped piece of itself. It doesn’t like this, and sets out to find its missing piece, singing:
Oh, I'm lookin' for my missin' piece
I'm lookin' for my missin' piece
Hi-dee-ho, here I go
lookin' for my missin' piece
It starts out on a grand adventure searching for the perfect piece to complete itself, while singing and enjoying the scenery. But after the circle finally finds the exact-sized wedge that fits it, it begins to realize that it can no longer do the things it used to enjoy doing, like singing or rolling slowly enough to enjoy the company of a worm or butterfly. It decides that it was happier when searching for the missing piece than actually having it. So it gently puts the piece down, and continues happily searching.