During a total solar eclipse, a 25-year-old 21st-century woman, Go Ha-jin (Lee Ji-eun), is transported back in time to Goryeo Dynasty. She wakes up in the year 941, in the body of Hae Soo and there, she encounters the many royal princes of the ruling Wang family. She initially falls in love with the gentle and warm 8th Prince Wang Wook (Kang Ha-neul), and later Wang So (Lee Joon-gi), the fearsome 4th Prince who hides his face behind a mask and is given the derogatory label "wolf dog." Meanwhile, rivalry and politics ensue among the princes, in a fight for the throne, as Hae Soo finds herself unwittingly caught between it all.

"If we are not from the same world, I will find you, My Soo." - Wang So An alternate ending for Scarlet Heart Ryo, where Hae Soo returns to the present after dying in Goryeo. After she regains her memories, she is never able to forget about Wang So, no matter how hard she tries. In the other world, the King has just passed away. He had been a good King.

An 18 year old girl is given a chance for a new life in the Goryeo Dynasty. Where does this opportunity take her?

This story picks up 10 years to the day after Zheng Xue Jing first acquired the Magic Screen in Episode 1 of the television series "Fox in the Screen" "Ping Li Hu" 屏裡狐 from Mainland China.