Li Zaixiang, a modern-day tutor, travels back in time to the Kingdom of Dajin and becomes the mentor to Li Zhuo, a young tyrannical emperor. For 12 years, he devotes himself to teaching his pupil, but a tragic catastrophe on the night of Li Zhuo’s wedding strips him of his status and leaves him confined to the palace. Amid dark palace conspiracies and a fatal incident at the hunting grounds, the two overcome countless crises and finally face their true feelings for each other.