Korea, 1950. A child’s vow to take care of his family marks the beginning of a lifelong promise spanning sixty years.

Oh Mal-Soon (Nah Moon-hee) is a 74-year-old widow that realizes she is becoming a burden on her family. As she is roaming the streets, she comes across a photo studio and decides to dress up for a self- portrait. When she walks out of the photo studio, she mysteriously turns back into her twenty year old self. Making the most out of this one in a lifetime opportunity, she changes her name to Oh Doo-Ri (Sim Eun-kyeong) and decides to make the most out of her youth.

In real life, Kwon Yoo is unemployed, but in the virtual game world he is the best leader. Kwon Yoo is then framed for a murder. With the help of hacker Yeo-Wool, he tries to uncover the truth behind the murder case.

In an insurance company, Yoon, who is an outsider, has a power to see people’s past and read their minds. Mr. Park, Yoon’s boss, assumes that she has some kind of special power, decides to test her ability. At very late night when everyone has gone home, Mr. Park brings Yoon to a storage room where there are full of case reports. Among them, Mr. Park picks three doubtful cases. He asks Yoon to tell him what exactly happened. Yoon, who senses some dark aura wandering around him, tells the story of each case. Every time Yoon finishes each case, the dark aura gets darker and bigger and Yoon tries to warn Mr. Park about it. Would Mr. Park able to escape from the dark aura?