Does the universe conspire to fulfill a decision once made? Is destiny a roll of the dice, a conscious choice, or the intricate result of countless conflicting threads of fate? All twins Kanba and Shoma understand is that when their terminally ill sister Himari collapses at the aquarium, her death is temporarily reversed by the penguin hat she requested. This resurrection is provisional and exacts a price: to keep Himari alive, they must locate the mysterious Penguin Drum. To achieve this, they must first uncover the links in a complex, interlocking chain of riddles that has ensnared their entire existence. They must unravel the knots connecting them to a mystifying diary and a baffling string of strangers and semi-acquaintances, each harboring their own secrets, agendas, and "survival strategies." Furthermore, for Himari to live, someone else's chosen destiny must be altered. It is a tale of love, fate, life, death... and Penguins!