Private detective Lin Mo loses his beloved cat, Jazz, when his agency is burned down by the mysterious "Immortals' Club." Forced to accept an invitation to the club's headquarters on Mirror Lake Island, he is shocked to discover that his guide, "Mirror," looks just like Su Qing, his fiancée, who died in an "accident" three years ago. Mirror reveals that the club pursues the mysteries of the universe, with "immortality" merely a byproduct, and tells Lin Mo that he must pass the core AI Ouroboros's test to learn the truth about Su Qing. Lin Mo passes the test in his quest for the truth and becomes "Candidate K-07." He learns that although Su Qing's body is dead, the club captured part of her powerful consciousness. Mirror is a simulation created from those fragments.
