Sally and Nick want to paint rainbows, but they don't know what colors to use, or what order to put the colors. And where do rainbows come from, anyway? The Cat in the Hat is not quite sure himself, but he knows someone who will know—King Kaleidoscope, ruler of Colorgalore! So it's off to visit the King in this funny, fact-packed book based on an episode of the PBS Kids show The Cat in the Hat Knows a Lot About That! featuring 3-D artwork on every page—and a pair of 3-D glasses!