Green Hippo is feeling sad because someone told him green hippos don't exist. His friends Frog, Elephant, and Giraffe try to cheer him up, but Green Hippo is too dejected to listen--it's easy for them to say such things, as Frog is the color he's supposed to be, Elephant is gray, and Giraffe yellow! Walking off on his own, Green Hippo suddenly notices the kaleidoscope of colors all around him in the meadow, and his sadness turns to happiness. He can't wait to share his discovery with his friends, who have their own surprise for him. In a touching story about friendship that doubles as a concept book about colors, Petr Horácek brings his own brilliant palette to celebrating the differences among us--and the gift of being yourself.