In the early days of the Republic of China, a mysterious murder at sea draws Zhang Haiyan and his partner into an investigation that quickly spirals into a dangerous conspiracy. What begins as a search for truth aboard the massive ship Nan'an becomes a fight for survival in a world of intrigue and betrayal.

“当朝左相”沈在野因他人计谋被迫迎娶和亲公主姜桃花，沈在野表面上是一个奸佞丞相，实则一心为国为民为天下；姜桃花为保小命绝境求生，两人互斗过，合作过，在一次次的危机中暗生情愫……
剧集根据白鹭成双小说《桃花折江山》改编。