After drinking an elixir that bestows him with immortality, a young Indian named Flapping Eagle spends the next 700 years sailing the seas with the burden of living forever. Eventually he grows weary of the sameness of life and journeys to the mountainous Calf Island to regain his mortality. There he meets other immortals obsessed with their own stasis and he sets out to scale the island's peak, from which the mysterious and corrosive Grimus Effect emits. Through a series of thrilling quests and encounters, Flapping Eagle comes face to face with the island's creator and unwinds the mysteries of his own humanity.