Princess Yona lives an ideal life as the only princess of her kingdom. Doted on by her father, the king, and protected by her faithful guard Hak, she cherishes the time spent with the man she loves, Su-won. But everything changes on her 16th birthday when tragedy strikes her family!

Yona and her friends leave the Water Tribe lands and meet a boy named Karugan in an Earth Tribe town near the nation's border. When they cross the border to take him back home, one of the Dragon Warriors unexpectedly collapses!