Sixteen-year-old Katy McLaughlin dreams of fulfilling her family legacy by working on her father's ranch in modern-day Wyoming. But Katy's father wants more for her, insisting that Katy go to college. Katy finds a wild mustang, which she names Flicka, and sets out to make her a riding horse. But, Flicka and Katy are more alike than she could have imagined. Like Katy, Flicka has a disdain for authority and is not about to give up her freedom without a fight. But, Katy's rancher father, the equally-willful Rob, sees nothing but trouble coming from the untamed animal and discourages his daughter from keeping her. Nonetheless, conflicted by a need to harness her own wild ways yet stay true to a free spirit within, Katy sets out to break through to Flicka and transform her into a riding horse.