Molly and her friends Sunny and Happy are fun, colorful unicorns. They live in the Enchanted Forest and attend Rainbow School there. From their favorite teacher, Mrs. Summerwind, they sometimes learn in class about what happens beyond the great, forbidden gate in the world of humans. Molly and her friends grow eager to experience this world for themselves. Only Moonlight, the mysterious unicorn, can help them with that. After passing many tests and proving their teamwork skills, their great adventure begins. Together with Moonlight, they overcome the great, forbidden gate and enter the human world. There, they help Tobias, a young horse farm owner, and his friends. In a dangerous nighttime operation, they rescue the horses from Farmer Greedyman, who keeps them under the worst conditions on his farm.