Toward the end of the WWII, Taro & his mother Kazue (Fumie Kashiyama) leave Tokyo, which the Americans have been fire-bombing. They retreat to safety in Northern Japan to stay with Taro's grandmother (Hiromi Nakahara) & two aunties (Meiko Kaji as Futae & Aiko Mimasu as Miyo) who run a bean-curd tofu company while men are off to war.
His grandmother tells him never to go in the barn, because it is haunted, so of course he checks it out & discovers Emi, Aunt Futae's hidden daughter. As her father was the enemy, Emi is at risk of being taken away by the authorities, so the women protect her & hide her existence, never having registered her birth so that she does not legally exist.
Taro deeply hates the enemy due to his susceptibility to the xenophobic tone of the era & having been taught that whoever does not hate Americans cannot love Japan, & who can blame anyone at a time when Tokyo was being burned down from one end to the other in an intentional policy of "kill as many civillians as possible!" But his friendship with Emi breaks down his prejudice, in an idyllic countryside beautifully photographed.