In a mythical land called Arth, the inhabitants of the ancient city of Arthdal contend with power struggles, while some encounter love along the way.
Eun-seom (Song Joong-ki) was born with a fate to bring disaster to Arthdal. Due to his mother’s struggles to save him, he goes through hardships and grows up. He appears again in Arthdal.
Ta-gon (Jang Dong-gun) is a war hero of Arthdal. He has paved the way for Arthdal to become a prosperous city nation and he is the most powerful person in Arthdal. He dreams of becoming the first king of Arthdal.
Tan-ya (Kim Ji-won) was born with the same fate as Eun-Sum. She is the successor of the Wahan Tribe. Going through hardships, she realized her mission. She lives under the highest honor and her ambition is to become a politician.
Tae Al-ha (Kim Ok-vin) is the daughter of the Hae Tribe Chief, Mi-hol, a woman whose ambition knows no bounds.