In suburban Tokyo, the Kobayashis – Mikio, his young second wife Natsuki, and his young adolescent daughter Eriko, who was borne out of his first marriage – live in a small flat above the family printing business. Mikio inherited the business and the flat from his father who passed away two years ago. Temporarily living with them is Mikio’s divorced sister Seiko, who is there until she decides what to do, which is in her mind – unrealistically – to go abroad to learn English. Their rather dull and staid lives are punctuated by Eriko’s pet parakeet having recently flown away, it which they are scouring the neighborhood looking for, and their neighbors organizing a neighborhood watch to keep out undesirables, namely foreigners who they believe are causing no good to their society. Into their lives stumbles Hanataro Kagawa, the son of their father’s old friend. Before they know it, Kagawa has talked his way into a job working at the print shop and room and board in their flat.

Theatre 1 (Observational Film Series #3) is a feature length documentary, which closely depicts the world of Oriza Hirata, Japan's leading playwright and director, and his theatrical company, Seinendan. By depicting them, the film leads the audience to revisit fundamental but timely questions: What is theatre? Why do human beings act?