On an isolated island with "memory trading" as its core industry, a man who lost his memory landed on the island in search of himself. His only clue was the broken image of a lighthouse and a hand that flashed repeatedly in his mind. Miss Yi, the chief memory weaver on the island, promised to reconstruct the past for him, but the implanted memory was as perfect as a lie. When Linzhou discovers a real lighthouse in the ruins of the island that is completely different from his "memory", he realizes that he is not a patient seeking a cure, but may be a prisoner trying to uncover the truth. In this sea of mist where true and false memories intertwine, his only salvation may be the truth that he is led to forget.