August 1914, while the German army is gaining ground in the North of France, four boys aged 10 to 15, Lucien, Lucas, Luigi and Ludwig are left behind during the evacuation of their orphanage. Without the protection of Abbé Turpin and the schoolteacher Leutellier, the Lulus are now stranded on their own behind the enemy front line. Soon joined by Luce, a young girl separated from her parents, they decide to reach the neutral country of Switzerland by all means possible... they embark on an adventure for which nothing has prepared them! They will discover that the supposed enemies can turn out to be formidable allies, like Hans, the German deserter with a big heart, Louison, the so-called witch of the village, Gaston, the grumpy clog maker or their new friend Moussa, a young Senegalese rifleman. The Lulus is a family movie that is innovative and demanding. It mixes reality with naivete, humor with emotion, intimacy with spectacle, and nostalgia with universality.