It is 2030, and an amazing medical breakthrough has made Alzheimer’s Disease a curable illness. The contract killers Ge and Song execute carry out daily missions for their organization. Ge appears cold-blooded and calm, but suffers from constant nightmares. As fragments of confused memories emerge during his missions, his unstable condition jeopardizes his fate. His cold-hearted partner Song saves him, and gradually they fall in love. Meanwhile, Ge realizes that one of the subjects he terminated was someone he knew from the past. They infiltrate the Brain Science Lab to find out the truth. There he learns that his memories are being manipulated by someone, and even more horrific, there is a conspiracy behind it. In a dystopian future where perfect brainwashing is possible due to the development of science, individuals feel confusion about their identity and become doubtful about the system while those with power dream of greater ambition.