Won-cheol of the National Intelligence Service of the Republic of Korea is offered a mission. Eliminating VIPs who participated in the operation to develop weapons of mass destruction in North Korea. Won-cheol is forced to accept the mission while thinking of her daughter 'Ah-reum' who is in danger - The secret operation of South and North Korean special agents begin.

The story takes place at the beginning of the 19th century. Goo Hae-Ryung is a historian who tries to fight gender stereotypes as her work is often looked down on. She meets Prince Yi Rim.

Lee Chung is a Prince of Joseon, but he has been taken hostage to the Qing Dynasty. He enjoys boozing, womanizing and gambling. He is also an excellent swordsman. His older brother Lee Young will succeed to the throne and brings Lee Chung to Joseon. He returns after more than 10 years. Soon, Lee Chung faces monsters that run rampant in the night.

When a crime organization from North Korea crosses borders and enters South Korean soil, a South Korean detective must cooperate with a North Korean detective to investigate their whereabouts.

On-yoo is an adult childhood cancer survivor. When he's not practicing with his boy band, Oh-yoo often volunteers at the hospital's pediatric cancer ward. One day, he recognizes the familiar face of an overdose patient.