The film is set in May 1940 in and around the city of Rotterdam, where the young bakers assistant (and aspiring amateur boxer) Vincent de Graaf meets the wealthy Eva von Heerle, the daughter of German refugees who've fled Nazi Germany. Eva is engaged to Dirk Lagerwaard, a wealthy older industrial whom she does not love, whereas Vincent wants to emigrate to the United States to find a cure for his sick brother. The two fall in love. As German troops invade the Netherlands, Vincent offers Dirk to bring Eva and her parents to Rotterdam resulting in a dangerous journey through the frontlines as Dutch and German troops clash in bitter combat. As the two reach Rotterdam, an ultimatum is delivered to the Dutch troops defending the city in which they are summoned to surrender immediately or face destruction, the Dutch soldiers refuse and Rotterdam is bombed, changing the future for everyone involved