根据韩战期间真实战事改编。1950年6月25日，北韩挥军越过三八线突袭南韩，三日攻陷汉城（今首尔），战线不断南进。在美军及联合国军支援下，南韩军逆势反击。美军指挥官麦克亚瑟提出代号为「铁铬行动」的仁川登陆计划，该计划急需一支大队的兵力从侧翼阻击扰敌、声东击西，通过长沙里切断北韩军的补给线。 由于任务本身极其艰钜，加上南韩国军当时兵力薄弱，无法抽调足够正规军支援，军方不得不把这项任务交付给772名学生兵执行，这些学生兵平均年龄只有17岁，仅仅接受了两星期的军事训练，在毫无实战经验的情况下投身战场。行军路上固然杀机重重，战友内部也诸多衝突，年少气盛，迸发出各种角力。 仁川登陆战前夕，长沙里登陆任务如期执行，这群徒有一腔热血但战力薄弱的学生们，无可避免地接受命运中最残酷的考验：穿越炮火与海浪， 浴血长滩，馀下部队身 陷敌军重重围剿，直至 弹尽粮绝，挣扎于阵亡与倖存 的分界线上… Based on the incre dible true sto ry of Jang sari Land ing Operation. When North Ko rea invades S outh Korea on June 2 5, 1950, the y pushed S outh Kore a and it s ally US Ar my to the sout hernmost  city. U.S. Ge neral M acArthur planned Operati on Chromit e, whic h would see the joint a llied forc es to take back a strategi c location of Inch on and in ord er for it to s ucceed, he  needed  a small battali on to flank t he North Kore an army and eliminate their s upply line at Jang sari be ach. Having l ost his fami ly on his ret reat awa y from Nort h Korea b efore the War, a mode l student Ch oi Sung-pi l enlis ts in the arm y to figh t for t he South. Ki Ha-ryun is  a rebelliou s youth fro m the Sout h who volu nteers t o fight i n the war. Al l of the 772 st udents an d youths are like them w ho are barely out of scho ol with only 2 weeks o f boot camp  training. T ask forc e commander Captain  Lee Myung-jun knows tha t it’s a long s hot, but he ha s no choice bu t to lead  them into a crucial miss ion. Meanwhile , US w ar corresponde nt Maggie  braves the dangers of the battlefiel d to repor t on the war in the frontl ines. S he feels e mpathy fo r the Kor ean student s who must go  into battle on behalf o f the veteran s oldiers for the ir country,  and tries to do what s he can on her end to res cue them. Wit h little ammo,  scant food sup plies and r aggedy  weapons, can the student s successfully carry out their m ission and ret urn home  safely?　 　根据韩战期间真实战事改编。1 950年6月25日 ，北韩挥军越过 三八线突袭南韩，三日攻 陷汉城（今首尔），战线 不断南进。在美军 及联合国军支援下，南韩军 逆势反击。美军指挥官 麦克亚瑟提出代号为「铁铬行动 」的