After the assassination of President Park, martial law has been declared. A coup d'état bursts out by Defense Security Commander Chun Doo-gwang and a private band of officers following him. Capital Defense Commander Lee Tae-shin, an obstinate soldier who believes the military should not take political actions, fights against Chun Doo-gwang to stop him. The conflict between the two grows while military leaders are holding their decision and Defense Minister is gone. In the midst of chaos, the spring of Seoul that everyone longed for heads to unexpected direction.

Navigating both the criminal underworld and law enforcement agencies, professional snitches called "yadang" provide covert information about the drug world to prosecutors and police. When a drug bust at a party attended by high-profile second-generation VIPs entangles those involved into a dangerous conspiracy, a seasoned yadang must do everything in his power not just to make it out on top, but alive.

Sang-hyun is always struggling from debt, and Dong-soo works at a baby box facility. On a rainy night, they steal the baby Woo-sung, who was left in the baby box, to sell him at a good price. Meanwhile, detectives were watching, and they quietly track them down to capture the crucial evidence.

After being kidnapped as a small child and raised by the five men who abducted him, a teenage boy is now forced to join their life in crime.

A determined detective continues his search for the truth behind Asia's largest drug organization and its elusive boss he has unfinished business with.

In 1999, a teen girl keeps close tabs on a boy in school on behalf of her deeply smitten best friend – then she gets swept up in a love story of her own.

Joon is arrested for the murder of the top student at his prestigious school. When he is released, Joon holds students accusing him of the crime in a room and forces them to reveal their dark secrets.

Ishigami comes home from work and discovers his wife dead. Just then, he receives a phone call from his wife and falls in utter confusion. Unexplainable things keep happening as Ishigami struggles to find his wife. Gradually, Ishigami realizes all his memories are gone and finds himself acting like someone else. What is his true identity?

A woman suddenly disappears. Her fiance then sets out to find her and, in the process, uncovers layers of dark hidden secrets.

On a live music radio show, a letter arrives from twenty-three years in the past. Through the letter, the first love and friendships of five friends are revealed.