The Im family was the royal family of Goryeo. They were well respected by all and treated their people with emerse respect. Who could've known that one flaw would tear them apart?

Im Donghae: The kind king of Goryeo. He was extremely kind hearted and wished the  best for his queen and children.

Im Jessica: The beautiful queen who would sacrifice anything for her beloved family.

Im Yoona: She was the known as the goddness of Goryeo. With her pale ivory skin and her glass like eyes, she was like a polecirain doll. She became torn between the love of her youngest brother and her foreign fiancé. She was a broken soul from the start.

Im Taemin: The younger brother of Yoona. He is bright and enthusiastic and shows a great love for his family. He shared a close bond with his sister and an untreatable friendship with his twin Kai. He was in love with Kwon Sulli, the daughter of governor Kwon Minho of  Goryeo.

Im Kai: Being the  youngest sibling from the Im family, he was treated as a child but tended to ignore it. He is suspiciously introverted and isolated but became an overprotective brother and fell in love with Yoona from the beginning. Knowing he couldn't have her, he became sick in the mind and obsessed with her.

The Xi family was the royal family of the nearby country of China. They were the most strongest and influential families of Asian royalty. When the Goryeo was threatened by Japan to war Im Donghae proposed a arranged marriage between her daughter and one the Xi princes in exchange of a powerful alliance that would save their country.

Xi Kris: The powerful ruler of China who would play the nearby countries like a game of chess. He evidently decides to make an alliance with Goryeo knowing one of his sons will produce an heir. Though he doesn't display his affection for his family often, he knows they are his pursuit of happiness. 

Xi Seohyun:  The wife of Kris and the mother of China. Unlike her husband, she detested  politics and hoped her children would become euphoric. 

Xi Luhan: He was the oldest son and strongly believes in love and hope. He immediately became attracted to Yoona after their engagement and only wishes to make her fall in love with him.

Xi Tao: Even though he knew he could've been the husband of Yoona, he chose to follow the rough path of war and became a general that won the heart of Kwon Yuri, the wife of Kwon Minho.

The household of Kwon was probably the second most noble family of Goryeo. Just in a blink of an eye everything that each one of them had was gone. Except one. They still had each other.

Kwon Minho: The trusted governor of Goryeo, and the best friend of the king himself, Im Donghae. 

Kwon Yuri: The wife of Minho, beautiful but cunning. She fought to seduce Luhan  but ended up falling in a forbidden relationship with Tao.

Kwon Sulli: The gorgeous daughter of Yuri and Minho. Best friend of Yoona and secretly hide feelings from Taemin.