It's summer on the prairie, a hot, oppressive summer that has everyone's temper flaring. While Yakari's family, eager to find the buffalo they are tracking, has moved some distance from the other Sioux, nature suddenly unleashes its rage, and a tornado tears through the main camp. Tipis torn, supplies scattered, the tribe must now rebuild... but there are also several people missing, blown away by the twister and perhaps injured or trapped. Yakari sets out to look for them...