Reinhard von Müsel leads the Galactic Empire to a decisive victory over the Free Planets Alliance at the Fourth Battle of Tiamat. Celebrated in the Imperial capital as a hero, Reinhard's triumph elevates him to High Admiral and bestows upon him the prestigious title of Count von Lohengramm. Meanwhile, Yang Wen-li quietly returns to the Alliance capital, reuniting with his close companions. Both leaders anticipate a much-needed period of peace. However, a treacherous scheme orchestrated by Duke Otho von Braunschweig compels the Imperial High Command to task Reinhard with an invasion of the Alliance using a formidable fleet of twenty thousand ships. As tensions rise, Yang discerns the impending danger and warns his superiors of the looming threat. The Alliance responds by dispatching three fleets totaling forty thousand ships to intercept the Imperial forces, setting the stage for a monumental clash reminiscent of the legendary Battle of Dagon. Despite facing overwhelming odds, Reinhard unveils a cunning strategy, but Yang remains one step ahead. The question lingers: will the Alliance leadership heed Yang's insights in time to avert disaster?