The movie Chestnut: Hero of Central Park follows the misadventures of two young sisters, Ray and Sal, who come across a Great Dane puppy while playing in Central Park. The girls take a liking to the puppy and decide to take him home with them, much to the consternation of their adopted parents who live in a luxury apartment complex that explicitly forbids dogs.
The girls struggle to keep their new pet a secret from their parents, who are constantly on the lookout for any signs of the pup's presence. They hide the dog, whom they name Chestnut, in a number of creative ways, including disguising him as a baby in a stroller and confining him to a makeshift doghouse inside their closet.
As time passes, the girls grow deeply attached to Chestnut and begin to see him as a member of their family. They train him to do various tricks and play with him in the park, always aware of the risk that they could be caught and forced to give him up.
One day, Chestnut becomes a hero when he helps to save a young boy from drowning in Central Park's lake. The boy's grateful family rewards Chestnut with a handsome sum of money, which the girls secretly use to purchase a new apartment where they can live with their beloved pet.
Chestnut: Hero of Central Park is an endearing family film that showcases the bond between humans and animals and the lengths that people will go to protect those they love.