Summer is approaching, and so is Tilly's first competition. After years of dreaming about being able to ride and compete, it's finally happening and it's all Tilly can think about! But before she can worry about her own performance, Tilly has to help new friends Brook and his black thoroughbred, Solo, overcome their nerves, and when she does, Brook reveals that he and Tilly have more in common than anyone could have guessed.