Byun Jae Wook is a short-tempered prosecutor with a propensity for violence, famous for his tough investigations and who only pursues the truth. When a suspect under his interrogation is found dead, Jae Wook is arrested, falsely accused of murder and imprisoned for 15 years .
While in jail, he plans out his revenge mission and finds the most talented criminals in the ward to help him out. Five years later, Jae Wook meets good-looking, brilliant con artist and schemer Chi Won in prison.
Feeling he could carry out his plan outside of prison, Jae Wook gets Chi Won acquitted, using his knowledge as a former prosecutor. Jae Wook’s ragtag team of ex-cons will now enact a revenge plan against the organization that framed him.
South Korean elite Air Force pilot Tae Hoon finds himself kicked out of his top-notch team and demoted into a combat unit after a cocky and dangerous air show demonstration. On the first day of his transfer to F15K, he meets Cheol Hui, the unit’s own top gun. Tae Hoon’s free-spiritedness and Cheol Hui’s rule-abiding ways come into conflict almost immediately. Meanwhile, Tae Hoon befriends the rest of the members of his new squad, including Se Yeong, whom he falls in love with. Tae Hoon continues with his antics until one day, a reconnaissance mission for the squad turns into an unexpected incident, ending in an untimely death and disappearance of a fellow teammate.
The unit receives an emergency announcement that an unidentified combat plane has entered into their territory, and Tae Hoon and Cheol Hui are forced to set aside their disagreements and lead their members to stop a war and rescue their missing comrade.
Early in his reign, King Se Jong accidentally causes the death of his in-laws and their slaves in an attempt to save them from his brutal father, King Tae Jong. Two young slaves, Ddol Bok and his friend Dam, survive but neither knows the other has. Ddol Bok blames the king and vows to kill him to avenge the deaths of everyone he loved. He spends several years becoming a great warrior. Dam, who has a photographic memory, becomes a court lady called So Yi, but she feels so guilty about her role in the other slaves' deaths that she is mute.
Ddol Bok returns to the palace under the name of Kang Chae Yoon in order to kill the king. However, he becomes embroiled in the mystery surrounding the deaths of several Hall of Worthies scholars. The deaths were caused by a secret society called "Hidden Root," which was created long ago by followers of Jeong Do Jeon, with the goal of giving more power to ministers and less to the king. King Tae Jong killed Jeong Do Jeon and all of his family except his nephew, Jeong Gi Joon, who is now the leader of Hidden Root and lives in disguise not far from King Se Jong.