Joseon Era, 1912

After the fall of the Joseon era to the Han Empire of China, a war broke out. Wanting to protect their daughter from harm, Emperor Gwangmu and Lady Bongnyeong pushed Hyerin inside a deep forbidden well at the backyard of Deoksu Palace. A magical well.

Soon after, the beautiful princess Gu Hyerin is banished from her traditional land and finds herself in the gritty reality of the streets of modern-day Seoul, South Korea. Shocked by this strange new environment, Hyerin is now trap in a chaotic world. But when Hyerin begins to fall in love with Taecyeon, a member of 2PM, who has come to her aid, she wondered if a forgotten princess from the past can really survive the view of romance in the real world.