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!

The Kingdom of Kohka triumphs over Sen Province, but Hak is gravely injured and Yona is unable to speak! Meanwhile, while tending to injured soldiers, Yun shows interest in the Sky Tribe's medical techniques. Advisor Keishuk invites him to Hiryuu Palace to learn more, but what is Keishuk's true motive?