Hong Kyung-Tak (Cha Seung-Won), a good-hearted citizen with high morals, returns from the army and gets hired as the body guard for KBB Security Company. Han Sung-Soo (Song Yil-Gook) is the president of KBB Security. When Sung-Soo attempts to bring down a politician through bribery, Kyung-Tak quits his job and joins another security company led by his friend. Park Yoo-Jin (Han Go-Eun) is a female bodyguard who works at KBB. A love triangle forms when she begins developing feelings for Kyung-Tak, while at the same time, Sung-Soo has feelings for her. When Yoo-Jin learns of Sung-Soo’s corrupt dealings, she decides not to give him a chance to be with her. The love triangle worsens when Kyung-Tak’s sister’s friend, Na Young (Yim Eun-Kyung), moves into the neighborhood and begins liking Kyung-Tak. Unfortunately for Na Young, Kyung-Tak only sees her as a little sister.