Evie and her Haflinger Pony Indigo take a magical journey through the tunnel of trees and arrive in the Rainbow Garden just in time for the annual Rainbow Blossom Festival. But as Evie and her kitten Sparkles lend a hand getting everything ready for the celebration, the Rainbow Girls' winged pony Corolla-who is supposed to pull the chariot in the parade-goes missing. Evie and Indigo join the hunt, and when Corolla is finally found, all the girls are in for a wonderful surprise!