As each chime sounds, Cara climbs faster up the steep bell tower. Eleven! She must be on the roof when the next bell tolls. Twelve! With a deep breath, and only half believing she will survive, Cara jumps off the church roof and into Luster, land of the unicorns.
In Luster, Cara meets many wonderful creatures, but the most magnificent of all is Lightfoot, a rebellious young unicorn. Cara's band of friends comes to include a hairy creature named the Dimblethum and the monekey-like Squijim. Together, they set out to reach the Unicorn Queen before the mysterious man who is following them does - to prevent the destruction of all unicorns forever.