In a corridor somewhere... Reimu Hakurei loses a battle and faints. She comes to and finds herself at Hakurei Shrine. She's unable to remember anything... What had she even been doing in the first place? Having regained consciousness, Reimu sets out together with her friend Marisa Kirisame to solve incidents. Reimu must now save Gensoukyou... From the various incidents, some of which she'd already solved before. —Reimu has no idea what she's in for.