The killer, the gay ‘Flying knife’ and the ‘Wild dog’ are assigned by their respective organizations. In the meantime, the two of them met by chance and found out that they were supposed to meet each other. Both are falling in love hiding the truth that they are killers, however ‘Wild dog’ has a secret that he even cannot tell to ‘Flying knife’. Finally the truth of both ‘Wild dog’ and ‘Flying knife’ are revealed because of order from each group. In the end, they are in danger being branded as a traitor from each of their group. ‘Flying knife’ and ‘Wild dog’ wish to make new family but there are many obstacles in darkness. Could they keep their love toward each other despite of rough adversity?