Middle-aged Hideo lives alone with an inflatable doll he calls Nozomi. The doll is his closest companion. He dresses it up, talks to it over dinner, and has sexual intercourse with it. However, unbeknown to Hideo, Nozomi was created with a heart. After Hideo leaves for work each day, Nozomi dresses in her maid's outfit and explores the world outside their apartment with a sense of child-like wonder. She encounters various city residents who metaphorically are as "empty inside" as she is. When Nozomi meets Junichi, who works at a local video store, she falls in love with him and gets a part-time job at the store. She learns about the world through the movies she watches with Junichi, but her happiness with him is interrupted by a dramatic turn of events. Director Koreeda has stated that the film is about the loneliness of urban life and the question of what it means to be human.