For eight months, Lee Kanghyun has searched relentlessly for the woman who saved his life. When he finally finds her, she is Yoo Seoyeon — raising a child alone, abandoned even by her own family. Then he notices something: the child's birthday lines up with the night they spent together. "I'll take responsibility for you and the child." The world's most dangerous man begins to move — to protect the woman he loves and the child who may be his.