A strange rumor has spread through Gensokyo: somewhere up in Heaven, there is a labyrinth full of treasure. Humans should not be able to reach Heaven, but those who have supposedly been guided there by a three-colored lantern. Reimu, Marisa, and Sanae each find a companion with their own objective and set out to discover the treasure's hiding place. Six adventurers carrying lamplight venture into a labyrinth that shimmers like a galaxy the moment you step inside.