Two sisters return home after a stay in a mental institution, only to face disturbing events and a strained relationship with their stepmother. As eerie occurrences unfold, dark family secrets begin to surface, blurring the line between reality and nightmare.

Min-ho's adulterous lover Se-hee is murdered in a hotel where only the two of them were present, and Min-ho is immediately singles out as the prime suspect. Insisting on his innocence, Min-ho hires the talented lawyer Shin-ae to defend him, and confesses to her that a car accident on the day before may be connected to Se-hee's murder.

The most important thing for Na-young, who has lived her entire life in a small seaside village, is taking care of her family and friends. However, her mother tries to sell their precious house full of memories, and her younger brother insists on moving to Seoul. While Na-young struggles to accept the changes, she comes across bowling and begins to spend more and more time at the bowling alley.

On March 26, 1991, five boys set off to the mountain to go frog hunting and never come back to their family. While a documentary producer, detective and professor try to solve the mystery of the incident, one of the boys' parents is a suspect.

Ju Yeong is a woman who longs for her ex-boyfriend but doesn't want to accept it. As she ends a short-term relationship with a very obsessive co-worker, her ex-boyfriend suddenly shows up as a new hire that she has to train. However, as rumors spread about her troubled relationship with the two co-workers, she finally realizes it was all her shortcomings that made it this way.

Anna learns in prison that her mother has passed away in Seattle. Prison officials grants Anna a three day furlough to attend her mother's funeral. Anna embarks on a long trip to Seattle. Hoon is a Korean immigrant who works as a gigolo. Hoon is now on the run from a wealthy client's furious husband. These two seemingly lost souls are about to share three memorable days together.

After losing their grandmother’s precious shoes, Su-min and her younger brother Dong-min accidentally fall into the netherworld where they encounter a mischievous band of kokdu, the mysterious guardians of the afterlife.

On the afternoon of the day before her school trip, Se-mi wakes up from her strange dream and heads to her Ha-eun. It was because she felt like she had to convey the feelings she had been holding back for a long time today. However, unlike her overflowing heart, the two keep falling apart.

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.

In a world where an AI programme allows people to communicate with their deceased loved ones, a flight attendant and a mother question the meaning of reality and humanity.