When Prince Ning Xuanzhou became a hostage in a rival country, he found himself forcefully rooming with Master Hua on the very first day. However, Hua Xiyu, who had been disguising herself as a man since childhood, mistakenly believed that Ning Xuanzhou, the secret spy leader, was a princess. Their fake friendship blossomed into a real romance. As for the villainous forces that sought to ignite a war between the two countries and tear them apart, they were joyfully defeated by the couple working hand in hand.
To protect her eldest sister, Yueling, the youngest princess of Dongyu, becomes engaged to Zhou Shiyu, the North Prince of Beishuo. During their journey to Beishuo's capital city, they face numerous assassination attempts. Their connecting jade pendant activates a Time Gate, allowing Yueling and Zhou Shiyu to repeatedly revive and strive to change their destiny while addressing their nation's challenges.