In a corner of the industrial area of downtown Tokyo, where the summer sunlight is reflected in the large riverbed of the Sumida River, the sound of a printing machine reverberates from the Kobayashi Printing Company. Kobayashi Mikio lives here with his young wife (Natsuki), his daughter from his previous marriage (Eriko), and his sister who is divorced (Seiko). In this diligent working family the only recent occurrence is the disappearance of Pi-chan, Eriko’s pet parakeet.

One day Kagawa Hanataro, who claims to be the son of a wealthy family that once gave financial assistance to the Kobayashi Printing Company, appears out of the blue. While adopting a humble attitude, Kagawa moves into the Kobayashi home, and the easy everyday life of the Kobayashi couple begins to unravel under the influence of Kagawa and the visitors that he brings with him.