"Just think of it as a really bad day." Joo-hee, a fitness trainer, moves to a women-only gym after experiencing numerous unpleasant incidents with male members at the gym. She finally returns to her peaceful and quiet life. But after closing time, someone knocks on the door of the gym asking for help. It's Choi Eun-seo, the last member who trained until the end. Instead of Eun-seo, who fled from her ex-boyfriend's stalking, Joo-hee goes down to meet the man. In a lonely alley she takes him with her and punishes him mercilessly until just before he dies. On a rainy night, Joo-hee takes a taxi home. The taxi driver talks to Joo-hee, who is wearing leggings. "Isn't it uncomfortable to be so tight?" Does the taxi driver know? That Joo-hee has not only killed someone once or twice. Can Joo-hee stop her from killing twice today? "I Didn't Mean to Kill" is the story of a killer, Joo-hee, who lives in the guise of an ordinary citizen. But in reality she only feels half as sorry for the dead. Because Joo-hee really didn't mean to kill them.

Middle school student Sang-min and his nine-year-old sister Yang-hee are waiting for their mother to come home from work. Sang-min calls his mother, but she doesn't answer the phone. Sang-min's father notices Sang-min's call and rushes to meet his children for the first time in three years, with his wife locked in the trunk of her car. As Yang-hee and Sang-min prepare dinner, the doorbell rings. Sang-min remembers his mother's instructions: "Always check to see if someone is at the door before you open it." She said this just a few days ago, her face filled with worry. When Sangmin looks at his father, he understands the meaning of those words.

Seong-ho, a famous architect who studied in Paris, France, was on the road to success after returning to his hometown. Fame came, as the architect displayed himself in television shows and magazine interviews. When his career reached its peak, a comment was written on his social media - asking him if he remembers a classmate passed away and claiming he caused the death. All the wealth, glory, and praise that had been with Seong-ho is breaking apart from then. With no clues on the accusation, the architect looks back on his past to find the culprit.

Five years passed since the case with serial killer Yi Byeongdo took place. Hayeong, who turned 16 years old, has been trying to overcome her trauma. But even with the continued effort of psychological counselling, she still is passing a confusing time. Pushed to be sensitive, by reaching adolescence and unexpected relocation, Hayeong gets stimulated by the violence taking place in her new school. As her inner shadow grows, what choice will Hayeong make after facing it?

Criminal psychologist Seonkyeong receives an unexpected call one day. Yi Byeongdo, a serial killer whose gruesome murders shook the world, wants to be interviewed. Yi Byeongdo, who has refused to speak to anyone until now, asks specifically for her. Seonkyeong agrees out of curiosity. That same day Hayeong, her husband’s eleven-year-old daughter from a previous marriage, shows up at their door after her grandparents, with whom she lived after her mother passed away, die in a sudden fire. Seonkyeong wants her to feel at home but is gradually unnerved as the young girl says very little and acts strangely...

Jeong-in, who returned to her hometown after divorce, is intrigued by Hye-jung, who moved in around the same time. Life in the remote countryside could be hard for a woman to live alone, but Hye-jung does not lose elegance and grace while growing flowers and eating well. Jeong-in, who admires Hye-jung's life more and more, learns her secret one day. The truth that Jeong-in has hidden for a long time is revealed...

Woo-jin lost his daughter three years ago in an uncertain accident. He, barely keeping his daily life in deep sorrow, got stumbled by his wife's untimely death. Woo-jin, who has nobody besides him, holds his wife's funeral and falls in despair. But then a single note brought him back; The note says: "The real culprit is still out there." Woo-jin, who had collapsed from the brink of life, rises again. To clear the mystery of the death of his daughter and his wife...

The moment that has frozen for 20 years begins to crack, then started collapsing. With the appearance of a half-brother, The memory of the day that no one thought could open suddenly unsealed and revealed. Arin's heartbreaking, but alluring story of twenty-seven scars begins now.

A brutally murdered girl was found dead in a park near a subway station in Seoul. Eight years passed, but the culprit has not caught. Detective Kang, who was in charge of the case, repeats the days of suffering and nightmares from guilt. On the eighth anniversary of the murder, a popular news host and the famous announcer killed. Soon, a dead woman's head delivered to the Seoul Metropolitan Police Department. A series of murders targeting women surfaced. A task force to catch the murderer initiated. Detective Kang, who is still suffering from past events, feels that those crimes are somehow connected with him and begins an independent investigation.

On a rainy Thursday night, a serial killer appears. "I," who has become homeless since the business went bankrupt and travels around the streets, collects articles on serial killers and studies his criminal behavior. There is a goal that I must achieve: to leave 600 million won for my only daughter Harin! To do so, I have to be murdered so that insurance money can be paid to my daughter. Finally, a rainy Thursday night comes. Can he meet the murderer?

Two boys find a beautiful world of magic and wonder when they find a magic marble in an old lighthouse. There they meet Mari and can escape from the growing hardships of their home lives...

What does it take to kill a husband? Mi-yeon secretly writes "How to Kill Her Husband" in her diary to stand another day of life. Her secret desire deepens, she is surprised to see her husband alive because she thought he was already killed by her. One day, her husband actually died. Was the husband murdered by his wife as Mi-yeon claimed? Or is there another true culprit?