Film distributor TOHO revealed its film release lineup for 2020 on Thursday, revealing that the anime film adaptation of Akihiro Nishino 's Entotsu-chō no Poupelle ( Poupelle of Chimney Town ) picture book will open in Japan in December 2020.

The film was previously slated to open this year.

Aeon Entertainment and planning, production, and marketing company Yoshimoto Kōgyō Co., Ltd. were considering collaborating on the film.

The story is set in a town surrounded by a wall that stands 4,000 meters (about 2.5 miles) tall. Because the town is full of chimneys, the air is always full of smoke. No one in the town knows what the sky looks like. On the night of the town's Halloween festival, a deliveryman accidentally drops the heart he is supposed to deliver. He cannot find the heart in the smoke and gives up. The heart continues to beat where it fell in the town of chimneys.