On Seon-woo is the head of the biggest company in Korea. He also secretly runs a private detective agency. On the other hand, Don Se Ra is a person with extraordinary vision and uses this ability to help people...

It tells an unpredictable 24-hour love story of the four-dimensional innocent girl Jung Saet Byeol who was once a troublemaker and the adorkable caring male store manager, Choi Dae Hyun, in the context of a convenience store. They have met each other accidentally 4 years ago, back then Saet Byeol asked Dae Hyun to buy cigarettes for them. Until now, Saet Byeol comes to the convenience store Dae Hyun runs for a part-time job, their hilarious romantic story starts.

Oh Hyun-Jae used to be a top criminal profiler. He solved many cases with his skills, but an explosion, caused by a serial killer, ended the life of his fiancé. After the horrific incident, Oh Hyun-Jae vanished and he now lives in seclusion. Meanwhile, Cha Soo-Young is police officer in a rural area. She has a special ability, which allows her to remember everything that she saw. Due to her special ability, she is selected as a rookie detective who will partner with Oh Hyun-Jae informally.

Through the course of their lives, a man and his first love are repeatedly separated from each other because of circumstances out of their control.

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.