Set in China during the Warring States period, Xin and Piao are two orphaned slaves of low status who share a brotherly bond and dream of becoming Great Generals. One day, they meet a nobleman who gives Piao the chance to take on an important duty in the royal palace of the state of Qin. As they part ways, Xin and Piao promise each other that they will one day become the greatest generals in the world. However, following a fierce coup d'état in the palace, Xin encounters a dying Piao. Piao's last words spur Xin into action, leading him to meet Zheng Ying, the young and soon-to-be king of Qin. Although they start off on bad terms, Xin and Zheng become comrades and embark on a path filled with trials and bloodshed. Zheng aims to bring all the warring states under Qin's rule, while Xin seeks to rise to the very top of the army ranks. Against a backdrop of constant tactical battles between states and significant political unrest, both inside and outside the palace, the two strive toward their monumental ambitions that will change history forever.