Adapted from the novel of the same name by Irish writer Sebastian Barry, it tells the life experience of a woman named Rosanne McNulty. Rosanne has lived in a psychiatric hospital for more than 40 years. She recorded her life experience in the hospital and the secret reasons why she was sent to the hospital in her diary. As the hospital was facing demolition, a doctor named Green began to evaluate her to decide whether she could return to society. In the process, he learned about her real life and found that although she suffered from the war, she still had hope and courage, believed in love, and finally her life was fulfilled in another form. The film reveals an unknown secret history of Ireland through her manuscript, reflecting the author's thoughts on the Irish War of Independence and the church's control and education of women.