As the air grows cold, a crystal-shaped seed lands on the Clangers' planet. Granny helps Tiny to plant it, and it quickly grows into a wonderful crystal tree. Other seeds fall, and soon there is a small forest of them. Mother Clanger has heard that these amazing trees can sparkle and glow, but none of the Clangers know how this is done until, completely by accident, Tiny discovers that music is the answer.