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!

While preparing to set up camp, Sinha comes across a stone statue of a dragon in the forest. When the statue's mouth starts to close down on Ao, Sinha slices it open and unintentionally releases an ominous spirit! How will Yona and her friends handle the ensuing havoc?