Grand Princess Li Yunzhen is rumored to live a decadent lifestyle surrounded by a harem of bodyguards. Cold and ruthless, she wields the real political power at court. The Emperor sends handsome Gu Xuanqing to the Princess' manor undercover as a royal guard to gather evidence of her corruption and topple her regime. But the more he gets to know the real princess, the less she fits the rumor, and he starts to fall for her.