In the Wanli Year of the Ming Dynasty, marauders team up with spies in the imperial court to frame the family of Lord Qiu, Minister of War. However, the youngest daughter Qiu Moyan is rescued by the warrior Zhou Huai'an. Before his death, Lord Qiu hands over the Ming Dynasty's coastal defense plan to his daughter, hoping to entrust it to someone who could shoulder the important responsibility of saving the dynasty. In order to obtain the defense plan, the marauders hunt down Zhou Huai’an and Qiu Moyan. The imperial court also lists the two as the most wanted criminals. To protect the defense plan and the descendant of the Qiu family, Zhou Huai’an looks for Dragon Gate Inn’s boss Jin Xiangyu for help. For the love of her life, Jin Xiangyu hides the defense map in the inn and transforms the inn into a dragon ship that stays away from the martial world, protecting the defense map until the right time comes. Unexpectedly, Qiu Moyan accidentally falls into the hands of the marauders. At the same time, the imperial court also sends Xu Yi, a crime-solving expert, to the ship to arrest Zhou Huai’an and Qiu Moyan. With different agendas, several forces fight to the death on this strange dragon ship.