“The Boy and the Heron” follows Mahito Maki, a young boy from Tokyo who flees the city with his father during WWII after his mother dies in a fire. Now living in the countryside, Mahito struggles with his grief and his new life. There’s also the pesky gray heron that never stops pestering Mahito through the family estate of his stepmother Natsuko (who is also his aunt).
Things get weird when Natsuko suddenly disappears one day. The heron, who is actually a strange creature with the face of a man (hidden inside the beak of the heron) taunts Mahito, telling him that Natsuko is at a nearby abandoned tower that Mahito’s granduncle was obsessed with and disappeared in. When the two enter the tower, they find themselves in an alternate fantasy world. That’s right, “The Boy and the Heron” is Miyazaki doing an isekai (Japanese for “another world”).
While in the fantasy world, Mahito encounters all sorts of fantastical creatures, like spirits, an army of parakeets, and a young woman with magical powers named Himi. All the while, he starts becoming friends with the heron — reluctantly. After a couple of adventures and encounters, the two face off against the parakeets and infiltrate their castle to rescue Natsuko, who is giving birth.