Gong Woo-Jin is a 30-year-old single man and he works as a set designer. Due to a trauma he experienced 13 years ago, he does not want to have a relationship with others. When Woo Seo-Ri was 17, she fell into a coma. 13 years later, she wakes up from her coma. Her mental age is still that of a 17-year-old, but she is now 30-years-old. Gong Woo-Jin and Woo Seo-Ri get involved with each other and fall in love.

Although born in the same year, two childhood friends end up being 13 years apart because they have aged surprisingly at different places (worlds) for some strange reason. Now Eom Hyeon Soo is a 31-year-old woman but Sung Hae Sung is still a 18-year-old boy. Cha Won Yooung is a chef also interested in Eom Hyeon Soo.

Scarlet Heart: Ryeo is the remake of Chinese drama Bu Bu Jing Xin that stars IU as a woman who gets time-warped back to the Goryeo dynasty, and becomes involved with a very large family of princes, some of whom are vying for the throne, or her affections, or both.