《开战日》是一部战争题材的电影，该剧以真实的事件改编，讲述的是二战时期德国军队穿过国界进入丹麦境内，丹麦日德兰岛的自行车联队与摩托车联队最先抵御德军先头部队的故事。

这部影片深度还原了二战期间丹麦与德国之间的战争，在德国装甲军集结的时候，丹麦士兵还在更换自行车的轮胎，两支军队从实力莎剧上来说相当大，在接到上级命令之后，自行车连队在公路上骑行，丹麦士兵从未看过任何的装甲车，他们对自己的机枪非常的自信，很快，这支部队便感受到了绝望，他们被树被高于自己的士兵所为困，自己引以为豪的机枪打不透装甲车的防御，中尉选择了果断撤退，自行车也成为了他们的逃跑工具，可即便如此也无法抵挡德国的铁蹄，影片用极度压抑的北欧风格讲述了这个真实的故事。

"Battle Day" is a movie about war. Adapted from real events, it tells the story of the German army crossing the border into Denmark during World War II, and the bicycle unit and motorcycle unit on the Danish island of Jutland were the first to defend against the vanguard of the German army

This film deeply restores the war between Denmark and Germany during World War II. After changing the tires of the bicycles, the two armies are quite large in terms of strength. After receiving orders from their superiors, the bicycle companies rode on the road. The Danish soldiers have never seen any armored vehicles. They are very familiar with their machine guns. Confident, soon, the troops felt hopeless. They were surrounded by trees and soldiers higher than themselves. The machine gun they were proud of could not penetrate the defense of armored vehicles. The lieutenant chose to retreat decisively, and the bicycle became Their escape tool, but even so, cannot withstand the iron heel of Germany. The film tells this true story in an extremely depressing Nordic style.