A Korean-style spy investigation show with a story about a top National Intelligence Service (NIS) agent. In his endeavor to uncover the internal traitor that brought him to his downfall, he confronts a much bigger enemy behind the organization. Han Ji Hyuk is the top field agent in the NIS. He is held in awe by his colleagues for his perfect record and skill at completing missions. He had been driving an organized crime syndicate into a corner when he vanished off the face of the earth, but he returns a year later to shake up the syndicate once more. Seo Soo Yeon is the head of team 4 of the Crime Information Center who is excellent at performing her duties and solving cases. She has great affection for people, and she especially cares for her teammates.

Se Young is the youngest head of the management team of Dreams, a cellar-dwelling baseball team. She's highly recognized for her perseverance and intense passion for the team. One day, Seung Su is appointed as a general manager. Although he's been working in the sports field, the teams he led to the championship were unpopular, and some of them were even disbanded after winning the league due to the financial difficulties of their parent companies. Would this unlucky new general manager be able to steer Dreams to the championship with passionate Se Young?

Diagnosed with hyperthymesia, Seo Jin Woo possesses an uncanny memory, which he uses to his advantage as a lawyer defending his wrongfully convicted father. But when Jin Woo is afflicted with Alzheimer’s, his only link to his father’s innocence begins to fray. With a mind that’s both his greatest asset and greatest liability, can justice prevail?

Hoon-Nam knows about love theoretically, but he rejects falling in love. Jung-Eum wants to fall in love, but, due to her difficult situation, she gives up on finding love. Hoon-Nam and Jung-Eum meet and develop a relationship romantically.

A desperate 35 year-old Young-sil is more than ready for full time job. And finally she gets a call from National security department as an intern. But her joy lasts no long, soon asked to leave. Accidently she discovers a secret about her boss and she suggest a deal of full time job to help him; secret spy.

Kim Gwan-Chul used to work as an accountant, but now he works as a chief for a company. He is man who follows his principles and uses common sense. He also stands up for those in weaker positions.

Gong Shim rents out her rooftop room to a pro-bono lawyer in order to fund her art study abroad, consequently turning her life upside down.