In the waning days of World War II, the isolated German island of Amrum, which the film is named after, is quietly torn in two. In the middle is Nanning (Jasper Billerbeck), a young boy whose zealous mother Hille (Laura Tonke) awaits the return of her Nazi official husband and the arrival of her baby, on the cusp of being born when the film begins. Hille is far from nurturing, more concerned about Nanning’s belief in the Nazi party than his experience as a young boy.