Xie Xuanyi used his modern knowledge to assist the Great Li dynasty for five years, only to be envied for his outstanding achievements and stripped of his military power by Empress Jiang Wanying. He stages his own death, hoping to spend his days fishing in peace. But unexpectedly, Tantai Fanyin, the Empress of Northern Liang, arrives at his door with 100,000 cavalry. This formidable rival, who has clashed with him nine times, is willing to entrust him with her military authority and national treasury, inviting him to build a new future together. Xie Xuanyi responds to internal and external crises with steelmaking, military training, and political reforms. Meanwhile, a diary reveals who truly deserves the credit, leaving Jiang Wanying filled with regret as she heads north. When the two empresses finally meet, which path will he choose?