The film's story takes place during World War II. After Mahito loses his mother during the firebombings of Tokyo, he and his father move to the countryside. There, Mahito's father gets remarried to his late mother's pregnant sister. As Mahito struggles with his situation, he encounters a talking heron and enters another world based on a promise that he can meet his mother again.
The cast in the English-dubbed version includes:
- Christian Bale as Shoichi Maki
- Dave Bautista as The Parakeet King
- Gemma Chan as Natsuko
- Willem Dafoe as Noble Pelican
- Karen Fukuhara as Lady Himi
- Mark Hamill as Granduncle
- Robert Pattinson as The Gray Heron
- Florence Pugh as Kiriko
- Luca Padovan as Mahito Maki
- Mamoudou Athie as Parakeet
- Tony Revolori as Parakeet
- Dan Stevens as Parakeet