In pre-World War II Tokyo, a young woman named Taki is hired as a housemaid for the wealthy and refined Hirai family. The household consists of the head of the family, Masaki Hirai, his beautiful wife Tokiko, and their young son. Taki quickly becomes an integral part of the household, meticulously caring for domestic duties and earning the trust of her employers. She especially forms a deep bond with Tokiko, who confides in her about the challenges she faces balancing societal expectations and personal desires. The tranquility of their lives starts to ripple with the growing tension and eventual outbreak of war, impacting everyone profoundly.

Years later, after the war, Taki documents her experiences and reflections in a journal that she leaves behind upon passing away. Her grandnephew, Takeshi, discovers the journal and delves into its poignant and revealing contents. Through Taki's writings, Takeshi uncovers pivotal moments that shaped both the Hirai family's history and his own understanding of his lineage. As he pieces together Taki's memories, hidden secrets and emotional complexities come to light, offering a vivid portrait of a bygone era and the nuanced relationships within a seemingly serene household.