It is about a little boy who runs outside after a rainstorm to try to find a rainbow. After he fails to find it, he imagines that one appears in front of him, swirling and whirling around him, to let him know that it wants to play. They then play hide and seek (and the rainbow hides in a flower bed, of course), and other games. The boy returns home to find that the sun is making a prism with the goldfish bowl in his bedroom, so that there is a rainbow on his bedroom wall (a rainbow of his very own).
The tale is very simple and charming, and the illustrations are great, so that kids of all ages will love it. I highly recommend this book for any boy or girl.