本片根据波兰著名同名小说改编，讲述了二战期间，华沙被纳粹德国军队占领，波兰童子军的年轻人们与德国占领者进行英勇斗争的故事。
　　Based on a well-known Polish novel with the same title the movie re-tells a true life story of a group of scouts called ''Szare Szeregi'' (Gray Ranks) during the Nazi occupation of Warsaw and the liberation of one of its members (imprisoned and tortured by the Germans) through a maverick military action in board daylight right under the enemy's nose known ''Action at the Arsenal'' which was the biggest single feat of the sort undertaken by a youth resistance organisation in all of occupied Europe during WWII.

　　乌克兰基辅国家歌剧院，一伙蒙面歹徒突然闯入演出大厅，挟持在场数百名音乐家和观众。未过多久，乌克兰特警部队迅速赶到，并按照既定战术突入进去。与此同时，几名神秘之人换上特警部队肩章，趁乱潜入歌剧院，救出被困的美国大使。神秘人之一的男主“无名”（约翰·大卫·华盛顿 John David Washington 饰）虽然一度顺利完成任务，却身不由己置身死地。当他再度醒来，则被告知失去原有身份，此后将加入一个名为“信条”的秘密组织，去执行一项阻止世界毁灭的重大任务。早在歌剧院时，他便见识了一次逆转子弹的奇怪现象。而如今着手的任务，似乎正与逆转的子弹乃至逆转的时间息息相关。
　　注定发生的必然会发生，所种何因，便结何果……