Kim Sun-woo is an enforcer and manager for a hotel owned by a cold, calculative crime boss, Kang who assigns Sun-woo to a simple errand while he is away on a business trip; to shadow his young mistress, Hee-soo, for fear that she may be cheating on him with a younger man with the mandate that he must kill them both if he discovers their affair.
Ahn Soo-ji and Lee Jae-joon, who are oblivious to each other's real profession as secret agents, are in an ill-fated relationship. Three years later, they accidentally meet targeting the same enemy.
Ji-hyeon is enjoying her life after a female sex-change operation. One day a boy knocks on her door claiming that she is his father. Her attempts to act like an ordinary father conflicts with her life as a woman.
