Mika returns to Kaltenbach for the summer, eager to reunite with Windstorm, but the stables are close to bankruptcy and the stallion is distracted by unexplained wounds and sudden escapes into the forest. There Mika discovers a mysterious white mare she believes may be a unicorn, and meets Milan, a young stranger trying to catch her. As a tournament with prize money approaches, Mika makes a deal that could help save the farm.