A little black hen finds a soft blue egg, which rapidly expands and starts to float. All the barnyard animals, including ducks, geese, donkeys, sheep, cats, dogs, and peacocks are needed to sit on the egg to weigh it down and keep it inside the barn. What hatches is a surprise to the animals and the reader. The book stimulates the imagination of children and shows the benefits of working together, even though the animals are very different from one another.