The killers Ge and Song execute daily killing missions for their "Father" organization, and at the same time, Ge is often awakened by fragments of memories in his head during sleep. During a chase, a déjà vu scene causes Ge Jun's brain to fluctuate, and he realizes that these memory fragments have a significant connection to his past. Ge begins to trace his identity, but Song is also involved accidentally. The two of them realize the true nature of the "Father" organization and discover the truth about the evil "memory transplant" being carried out by the organization..