The story of the relationship between two families, based on the traditional Korean Cinderella folktale about Kongji and Patji. The Kongji family is poor but kind, while the Patji family is rich but selfish.

The cold and no-nonsense Director Han feels the stirrings of love for the first time when he meets Choon Hee. However, his subordinate Joong Do happens to be her first love, and he still has feelings for her. The two men begin a battle to win her heart.

Kim Kwang Ja is an ordinary 42-year-old housewife who has spent most of years devoted to her gruff husband and indifferent daughter. When she discovers the music of a popular idol boyband, she becomes a fan of the lead rapper, Jin, and finds new joy in her life.

Secret Investigation Record is based on cases detailed in the Annals of Joseon History with a bizarre twist; these incidents incorporate mysterious, supernatural elements that cannot be explained through science. Kim Hyung Do is an inspector of the state whose single-minded focus on his investigations into administrative misdeeds bring him into direct contact with these strange mysteries. Heo Yoon Yi is a government employee who aids him and attempts to understand these scientific impossibilities with an open mind, in contrast to his cynicism.

Ha Na and Doo Na were twin sisters who were very close to each other until Doo Na died a terrible death. One day, the usually bright and energetic Ha Na finds herself changing. She has superhuman strength and can do things that nobody can. Ha Na realizes that Doo Na's spirit has inhabited her body.