Princess Yona of the Kingdom of Kouka, with her unusual red hair, has lived a comfortable life in Hiryuu Castle protected by her father King Il, who hates conflict, and her childhood friend and guard, the young general Hak. Yona is overjoyed when her cousin Soo-Won, whom she has loved since childhood, arrives for her sixteenth birthday banquet.

“We'll go anywhere as long as it means you'll live.” As Yona is dazed by the suddenly rebellion at the castle, Hak runs to her rescue. Also known as the “Thunder Beast of Kouka Kingdom”, Hak protects Yona, and with a single lightning-quick strike from his blade, he dispatches the mercenaries attacking them on after another.

Hak is accused of murdering King Il. In order to protect Yona and the Wind Village, he gives up his title of chief and decides to wander alone.

In their search for the Blue Dragon, Yona and her friends visit a hidden village carved from stone. Though Ki-Ja insists the Blue Dragon is there, the villagers claim there is no Blue Dragon.