Cumulus, a bored and lonely cloud, decides to become an artist, creating ephemeral "sky-paintings" that appear for only a moment. After some practice, he learns to sculpt intricate and colorful images using sunlight and shadow, such as castles, sheep, leaping rams, dragons, and even a smiling whale. People on the ground begin to notice and marvel at his fleeting masterpieces, bringing wonder and joy, while Cumulus finds happiness and purpose in his unique artistic endeavor.