After immigrating to America and being abandoned by his own mother, Gon is raised to become a hit man. One day during a job, Gon accidentally kills a young girl and is plagued by guilt over killing an innocent child. His boss gives the despondent hit man a new job - to kill the young girl’s mother. Gon’s new target, Mo-gyeong, works as a risk manager at an investment firm. The grief-stricken mother buries herself in her work without knowing that she is in the heart of a dangerous conspiracy. Then, she meets a man who wants to tell her the truth behind the death of her child.
