Brad Martin, a famous reining expert, visits Half Moon Ranch with his champion horse, Little Vixen. Kirstie adores the horse but is suspicious of the man - especially when she sees him getting close to her mother. She's heard he's fallen on hard times and is worried he's after a share of the Half Moon profits.

Her worry turns to alarm when a sudden fire traps Little Vixen in the barn. Is Martin to blame? If so, why would he put his own horse in danger? Kirstie aims to untangle the truth from the lies...