Summer vacation with Ostwind, Mika is overjoyed. But then she discovers strange injuries on Ostwind's belly. To make matters worse, Kaltenbach is on the brink of bankruptcy! With a heavy heart, Mika decides to participate in an eventing tournament with a substantial prize money at stake. However, during training, Ostwind suddenly runs away. Mika follows the black stallion deep into the forest, until a magically graceful gray mare appears from the thicket. The two horses dance around each other affectionately. Suddenly, a strange boy named Milan appears. He claims that the mare has escaped from him and that he can help Mika win the tournament. What is the truth about Milan? Can Mika save Kaltenbach?.