Sal (Makenzie Vega) and Ray (Abigail Breslin) were two little orphaned girls when they found a Great Dane puppy abandoned in the middle of the road. After Sal saves it from getting run over by a truck, the girls decide to adopt the puppy and name him Chestnut. Soon, a couple named Laura (Christine Tucci) and Matt Tomley (Louis Ferreira) adopt them, and they move into their new home in New York City. Unfortunately, the apartment building doesn't allow dogs, so Sal and Ray must hide Chestnut from their adoptive parents to prevent the risk of him getting sent to the pound where he would be euthanized.
Chestnut: Hero of Central Park provides examples of:
- Affection-Hating Kid: Downplayed, but Sal and Ray appear to not like when adults kiss their cheeks out of affection. When Ray tells Sal that Janey said their new adoptive parents would kiss them, Sal assures her that she’s only trying to scare them. The girls stand in shock when Laura starts kissing them on the cheeks when she first meets them.
- Artistic License – Animal Care: The girls feed Chestnut food like hot dogs. In real life, while hot dogs aren't inherently toxic to dogs, they contain high fat and sodium content, and they shouldn't be fed to them regularly.
- Bait-and-Switch: The opening starts with Sal giving commands like “sit” or “stay” while saying, “Good girl!”, leading the audience to believe that she’s training her dog. She was actually giving those commands to Ray, her younger sister.
- "Be Quiet!" Nudge: Sal slightly kicks Ray’s foot to stop her from telling Mother Agnes that they found a puppy.
- Big Applesauce: The girls get adopted by a couple who live in New York City.
- Big Friendly Dog: Chestnut is a Great Dane and is very friendly to the girls.
- Big Sister Instinct: Sal is very protective of Ray and always comforts her when’s sad or scared.
- Cool Big Sis: Sal is a caring older sister to Ray and constantly looks out for her.
- Distinction Without a Difference: Sal tells Ray that she shouldn't be afraid of sleeping alone at night because it is the same as the day, only darker.
- Eek, a Mouse!!: Exploited. When Chestnut slips out of Sal’s grasp and lands under the dinner table, she screams out, “Mouse!” so that the orphaned girls would pull their legs up from under the table, and she can grab and hide the puppy.
- Ethnic Menial Labor: Rosamaria is Hispanic and works as the girls’ maid.
- Evil-Detecting Dog: Chestnut growls and attacks The Central Park Robbers when they break into Tomleys’ apartment. His size intimidates them and manages to scare them off.
- Fake Faint: Ray pretends to Faint in Shock as a distraction so Sal can quickly hide Chestnut before Mother Agnes sees him.
- Fright-Induced Bunkmate: Ray is afraid of storms and the dark, so she likes to sleep with Sal in her bed.
- Fur Pattern Naming: Sal names the puppy Chestnut because he’s brown and little, like a chestnut.
- Gender-Blender Name: Sal (technically a unisex name, but is mostly associated with males) and Ray. Downplayed in Sal’s case, as it is a nickname for Sally Anne.
- Gentle Giant: Chestnut is a Great Dane who is friendly and playful.
- Good Parents: Laura and Matt Tomley are very patient and loving parents to Sal and Ray.
- Good-Times Montage: There’s one montage where Laura, Sal, and Ray have fun in New York City, and another montage with Sal and Ray having fun with Chestnut.
- Gratuitous Spanish: Rosamaria is Hispanic and does not speak that much English, so her dialogue is mainly in Spanish.
- Happy Ending: In the end, The Central Park Robbers get arrested and the girls get to keep Chestnut and live with their loving adoptive parents.
- Happily Adopted: Sal and Ray get adopted by Laura and Matt Tomley, who are very loving and doting parents to them. Although it takes them a while, the girls begin warming up to their adoptive parents and eventually call them “mom and dad” instead of “Mr. and Mrs. Tomley”.
- Heh Heh, You Said "X": When Sal and Ray try explaining to Rosamaria that she needs to take Chestnut to the park to poop while they go to school, Rosamaria giggles at the word “poop.”
- No Animals Allowed: Trundle Buildings does not allow dogs, which is one of the reasons why Sal and Ray have to hide Chestnut.
- Orphan's Plot Trinket: Ray keeps an old photo of her and Sal’s mom for sentimental value.
- Please, Don't Leave Me: When Sal plays with Chestnut alone one day, she sees Ray crying on the front steps because she didn’t know where Sal was. Ray begs Sal not to leave her and Sal assures her that she won’t. In the climax, Sal decides to run away with Chestnut without letting anyone know. Ray doesn’t take this well and worriedly tells Laura and Matt, “She’s gone! She’s gone without me!”
- Plot Allergy: Sal and Ray’s adoptive father, Matt Tomley, is allergic to animals (especially dogs and cats), so he sneezes whenever Chestnut is near him.
- Pooping Where You Shouldn't: Discussed. When they enter their new home after being adopted, Ray asks Sal where Chestnut is going to poop. Later, Laura gives the girls a tour and shows them the balcony in their new bedroom. Ray excitedly exclaims, “Sal, a place to poop!” Laura has a surprised and confused reaction and promptly gives the girls a tour of the bathroom.
- Powder Gag: Chestnut dumps a bag of flour on The Central Park Robbers from upstairs.
- Road Apples: A man accidentally steps into Chestnut’s pile of poop, causing him, the girls, and Rosamaria to react in disgust.
- The Runaway: Sal runs away with Chestnut as a desperate attempt to find a new place where they can be together.
- Secret Pet Plot: The main plot is Sal and Ray having to hide Chestnut from their adoptive parents.
- Shoo the Dog: When the police finds Sal and Chestnut under the Central Park bridge, she tries to make Chestnut run away so that he doesn’t get taken away. Chestnut refuses to leave her, so she throws his favorite stuffed toy for him to fetch it, then goes away with the police officers.
- The Stool Pigeon: Janey appears to have a reputation as a tattletale. When Sal introduces the other orphan girls to Chestnut, she tells Janey not to tell anyone. Later, when Mother Agnes tells Sal and Ray to come to her office, all of the orphan girls turn to Janey and she insists that she did not tell Mother Agnes about Chestnut.
- Toilet Humor: The movie has a couple of jokes that involve pee and poop, with Chestnut being the main source.
- Tropey, Come Home: Sal ends up abandoning Chestnut at Central Park out of fear that the police officers would take him away. Once she gets home and Ray reveals that their adoptive parents have agreed to keep him, she immediately feels bad and is desperate to find him again.
- Two Men, One Dress: The girls dress up as two halves of a horse as their Halloween costume (with Ray secretly holding Chestnut). They later use this costume to disguise Chestnut in public.
- Urine Trouble: When Mother Agnes breaks the news to the girls that they are getting adopted, Chestnut ends up peeing on the floor. Sal makes Ray pretend to Faint in Shock to distract Mother Agnes so she can hide the puppy.
