Kwon Do-Hoon (Jang Hyuk) is married to Kang Yoo-Ra (Jang Na-Ra). He is a secret agent for the NIS (National Intelligence Service) and a veteran sniper with a quick and highly accurate shot. By day, he disguises himself as an ordinary employee for a trading company. Even his wife Kang Yoo-Ra believes he holds an ordinary office job. Kwon Do-Hoon is busy with his work, so he is unable to spend much time with Kang Yoo-Ra. Nevertheless, he loves his wife more than anything else. Meanwhile, Kang Yoo-Ra always dreamed of having a perfect family. She met Kwon Do-Hoon and married him. She works as a housewife and does it well, but she has a secret that nobody knows about.