A man is killed after a struggle with an unknown man at home. Another man suffers from thinking he will never be better than his higher-achieving brother. The man who is murdered is Geun-ho Kim, and the other is Geun-bae Kim, or Alpha One, Geun-ho's younger brother and a man of unparalleled talent in the art of disguise. Geun-bae is raised with the belief that he is a nobody compared to his intelligent brother and runs away from home. He makes a living out of his skill in disguise, encouraged by Geun-ho who believes he can become a great actor. One day, he visits his brother and discovers him covered in blood. Masking his brother's death as his own, Geun-bae lives in disguise as his brother. He chooses life as a fake to uncover the truth.