Yakari, a young Sioux Native American boy, sets out on a spectacular journey to rescue his best friend, Little Thunder, who has been kidnapped. Along the way, Yakari encounters various challenges and dangers, but with the help of his talking horse, he must overcome them to reunite with his friend.

While his friend Buffalo-Seed is in a deep coma and Rainbow reveals her shaman skills by keeping him alive, Yakari gallops off with Little-Thunder in search of the only living being capable of bringing him back to life: Buffalo-Seed's totem, the imposing, fantastic and dangerous Thathanka!