A bizarre phenomenon is occurring in Gensokyo. In the middle of summer, untimely rain and hail fall in the Forest of Magic, snow blankets Hakugyokurou, the Scarlet Devil Mansion is enveloped in a cloudy, dense haze, and the Hakurei Shrine is leveled by a sudden earthquake. Throughout the game, Reimu and the other protagonists set out to investigate the source of the strange occurrences. (Touhou wiki)