Jay, a promising young writer, is about to publish her new book. Geonwoo, Jay′s roommate and lover, works as an English instructor at a private institute and silently assists Jay. Both of them care about each other and are happy as they are. However, Jay’s unplanned pregnancy brings huge changes, causing conflicts between the two.

The flight scheduled to leave Incheon International Airport for New York makes an emergency landing at Gimhae Airport due to engine problems. As the passengers will take an alternative flight the following day, they are staying at a hotel provided by the airline during a layover. While staying an unscheduled night at the same hotel, they have an unexpected experience.

Kyung-hak, who has been studying to become a police officer, is forced to pay back his mother’s debt of $20,000. Already struggling and having to work part- time while studying, Kyung-hak is now forced to make big monthly loan payments on top. Eventually, Kyung-hak stops studying and becomes a deliveryman to make ends meet. Meanwhile, cracks start to form in his relationship with his beloved girlfriend Hye-jin.

After a high-ranking North Korean official requests asylum, KCIA Foreign Unit chief Park Pyong-ho and Domestic Unit chief Kim Jung-do are tasked with uncovering a North Korean spy, known as Donglim, who is deeply embedded within their agency. When the spy begins leaking top secret intel that could jeopardize national security, the two units are each assigned to investigate each other.

Young-jin doesn't get a chance to get a promotion because she is a woman. On the other hand, Jun-seul easily gets a job as a manager with the power of connections.

An eccentric, triple board-certified virtuoso surgeon leaves a top job in Seoul and ends up at a provincial hospital, where he mentors young doctors.