故(gù )事以大晟北境战事为(wéi )背景(jǐng ),苍狼王八万铁骑来犯(fàn ),顾山(shān )河领五千步兵迎敌,深(shēn )陷绝(jué )境。老将铁向权袖手旁观,监(jiān )军王挥月暗中通敌,构陷将(jiāng )士,按原结局,顾山河所部全(quán )军覆没,家族蒙难。太史令沈(shěn )文远(yuǎn )因鸣冤获罪,临刑时借(jiè )史书(shū )之力穿越回悲剧前夕(xī )。他主(zhǔ )动向顾山河示警,留在(zài )军中(zhōng )出谋划策,献策突围,奇(qí )袭敌(dí )粮,稳固军心。女医佐柳(liǔ )千羽(yǔ )也逐渐放下戒备,与众(zhòng )人并(bìng )肩作战。顾山河忍辱游(yóu )说铁(tiě )向权换来援军,沈文远设计(jì )揭穿王挥月通敌罪行,获取(qǔ )敌军情报。决战之时,陈敢率(lǜ )三百人死守营寨掩护主力(lì )转移(yí )。沈文远与柳千羽退守(shǒu )背阴(yīn )山,凭奇计坚守待援,奋(fèn )力扭(niǔ )转全军覆没的悲惨结(jié )局。