Kim Sojin lived an intense everyday life as an oriental doctor. However, after losing her life in a fire accident, she woke up again in the Goguryeo period as the daughter of the Jeolnobu Yeon Clan 'Yeon Woohee.' Although she was born into a noble family, war breaks out every day in this era! And now that she's twelve, she's going through a political marriage?! "You must be very surprised. Damdeok didn't tell you anything?" "If it's Damdeok..." Of all things, my marriage partner is someone who everybody in South Korea knows about, that 'Gwanggaeto The Great'? "I... I'm not going to marry you!" The blooming love story between the greatest king in history and the woman who remembers the 'future'.