Dream of the Emperor.

Kim Chunchu is the grandson of King Jinji, but when his grandfather is overthrown, Chunchu is denied the chance to become a successor to the throne of Silla. He later meets Kim Yushin, and the two men begin a friendship. Chunchu later becomes King Muyeol, the 29th Korean monarch who leads the unification of three ancient kingdoms - Goguryeo, Baekje and Silla, while Kim Yushin becomes one of the greatest generals in Korean history.