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.

The words of god conveyed to Yona through the priest Ik-Soo are to find the four Dragon Warriors of Kouka Kingdom's Legend of the Four Dragons

The five search for the green dragon warrior using Shin-Ah's farsightedness to scout ahead. They encounter a dilapidated village and a sickly man who criticizes the late King Il. Meanwhile, Su-won visits Chishin, the capital of the Earth Clan, and meets with Lord Li Geun-Tae, who is not impressed by Su-won. Su-won declares they will hold a war-game festival at Chishin in a week.

The war game is held. The participants are divided into teams with Su-won and General Geun-tae leading the white and red teams respectively. The objective: to score the most points by breaking the plates of the other team. Su-won's strategies and hidden ferocity impress Geun-tae, whose team manages to win more points than the white team despite all their plates being broken. Su-won leaves the city with his cohorts, having stimulated demand for Geun-tae's wife's tea in a neighboring land, re-invigorated production in the earth tribe's mines, and inspired the earth tribe's people anew of their leader's strength.

Yona and her companions reach Awa Port. Hak enters the city alone and without realizing it, meets the green dragon warrior, Jae-ha. Jae-ha moved to the city thirteen years ago and joined a band of good pirates lead by Captain Gigan. With the help of Jae-ha's jumping power, they sink the drug-carrying boats which belonged to the lord of the region, Yan Kumji. Jae-ha senses that the white and blue dragons have come to the city. As he wishes to avoid his destiny, he quickly disappears whenever they are near. When a citizen was harassed by corrupt officials, both he and Hak help. After meeting Hak, Jae-ha decides to recruit him.

"Miss, what do you want to do with the Four Dragons?" Yona and her companions continue their journey to find the fourth and final "Yellow Dragon" when they encounter a traveler named Jeno. He is the "Yellow Dragon" they have been seraching for.

ona and the gang head to a hot springs hotel, where they are greeting by the owner, an old women who always dozes off. Later on, Jae-Ha wonders why Kija has not entered the men's bath, discovering that Kija has a scar on his back shaped like claw marks and coming to the conclusion that the previous white dragon warrior scarred Kija's back.