Kaito Kuroba's father, a notorious thief known as International Criminal 1412: the Phantom Thief, was frequently absent during his high school years. After his father's mysterious death, Kaito discovers his true identity and learns of his refusal to assist a group in obtaining an unusual stone called the Pandora Gem. This stone supposedly grants eternal life to its possessor and shines like a tear during the passing of the Volley Comet. Determined to prevent the organization from getting their hands on the gem, Kaito adopts his father's alias and sets out to locate it. He only has a few breadcrumbs to follow, including the gem's red glow during the full moon and its status as a doublet, concealed within a larger stone. Kaito embarks on a treacherous quest to acquire precious gems with complex histories, all of which are closely guarded. He always returns the gems the day after the full moon, searching for clues to the Pandora Gem's whereabouts.