A surprising birthday message - from her horse - and it's not even her birthday. A mysterious hoofprint on her bedroom window. What is going on?
Eleven-year-old Isabelle senses something BIG is going to happen. Never in her wildest dreams did she imagine just how big.
When a shimmery chestnut mare knocks on her window and invites her on a ride, she discovers a shocking truth. She's a horse child - human by day, horse by night.
Soon she's trying to juggle two worlds - and explain to her friends why she can't do sleepovers. Sometimes she's not sure where she fits in.
And on top of it all, a mysterious person seems to be following her. Do they know who she is? And what do they want with her?