Krista learns that a gang of horse thieves has stolen several of the famous wild ponies that live on Hartfell moor. She returns to the magic place on the cliff path to ask Shining Star for help. They track down the gang as they plan another raid, but events run out of control as the whole herd of ponies runs towards some dangerous cliffs.

How can Krista and Silver Star save the ponies from a fatal fall?