Maggie Atwood and Becky McCabe, mother and daughter, both champion riders, vowed to never, ever, go up against one another. Until the tense, harrowing competitions leading to the Paris Olympics. Mother and daughter share a dream: to be the best horsewoman in the world.

When Piper Mills was twelve, she helped her grandfather bury a box that belonged to her grandmother in the backyard. For twelve years, it remained untouched. Now a near fatal riding accident has shattered Piper's dreams of Olympic glory. After her grandfather's death, she inherits the house and all its secrets, including a key to a room that doesn't exist, or does it?

Seventh grader Abby St. Clair is eager to start another season with her elite riding team at Saddlehill Academy boarding school, competing against her new stepsister--until she starts getting anonymous messages threatening to expose the secret she is desperate to hide.