Every day, Heather's grandfather signals her from the old lighthouse where he lives. But when a wild storm strikes, and there is no signal, Heather knows something must be wrong. There is only one way to reach her grandfather. Heather must saddle up her fiery pony, Caspar, and ride like the wind - across the stretch of wet sand between the mainland and the lighthouse. Heather trusts Caspar with her life, but can her storm pony possibly outgallop the incoming tide?
