In Paris, in the 30s, orphaned boy Hugo lives in the walls of the Gare Montparnasse railway
station.
By looking through the gaps in the big clocks, he can watch all the people that work in the
station, like Inspector Gustave and his dog.
Gustave has a bad leg that requires him to use a brace to walk, and he's obsessed with
catching thieves, especially children that he can send to the orphanage.
There's also Labisse, the book shop owner, Lisette, the florist Gustave has a crush on,
and Georges, the toy maker who is sometimes visited by his goddaughter Isabelle.
One morning, Hugo notices Georges has fallen asleep and tries to steal a clockwork mouse
from him.
However, Georges was only pretending and catches Hugo in the act.
Knowing the kid has been stealing from him for a while, he makes Hugo empty his pockets,
revealing all the clockwork parts from the toys he's taken and a curious little notebook.
Georges opens it and is impressed by the notes on clockwork Hugo has taken, however he also
freaks out when he finds the drawings of an automaton.
He doesn't believe Hugo when the kid says he didn't steal the notebook and sends him
away, calling him a thief.
Hugo doesn't want to leave without the notebook, but Gustave hears the word "thief" and begins
chasing Hugo with his dog.
They run through the whole station, and Hugo finally manages to lose them by climbing on
a ceiling platform while Gustave's leg brace gets stuck on a train door.
Afterward, Hugo goes back to his home in the walls to maintain the station clocks and keep
on people watching.
At the end of the day, when Georges closes his shop, Hugo goes to see him again to ask
for his notebook, but Georges promises to burn it.
Hugo decides to follow Georges all the way to his home, only to find himself left outside.
Seeing Isabelle in the window, he asks for her help, so she comes out and listens to
his story.
Isabelle promises to rescue the notebook because she likes the idea of secrets and adventures,
but Hugo needs to go home before they're found out.
When Hugo returns home, he cries as he stares at the automaton from the drawings.
This all started when Mr. Cabret, Hugo's widower father and clockworker, found an abandoned
automaton in the attic of the museum he worked at.
While Hugo learned the trade, he and Mr. Cabret worked hard to fix the automaton, but they
couldn't make it work without the heart key that it was missing on its back.
One night, Mr. Cabret died in a fire, so Hugo was forced to live with his alcoholic uncle
Claude, and all he manages to take with him was the automaton and the notebook where they
documented their progress.
Claude didn't send Hugo to school, instead, he taught him his own job, which was taking
care of the station clocks.
Shortly afterward, Claude disappeared, but Hugo kept on maintaining the clocks in order
to live in Claude's room without anyone noticing he was gone.
To survive, he stole food from the station shops while making sure to avoid Gustave at
all costs.
The next day, Hugo goes to see Georges again, but he's presented with the ashes of the burned
notebook.
Hugo runs away in tears and bumps into Isabelle, who has something to tell him in private and
drags him into the book shop.
After meeting Labisse, Isabelle tells Hugo that Georges didn't burn the notebook, it
was all a trick.
She also explains the notebook made him so upset that he cried, and her advice is to
try again while being steadfast.
Hugo goes to see Georges once more and refuses to leave, thus Georges decides to give him
a test.
Hugo must fix a clockwork mouse and impresses Georges with how quick he can work, so he's
accepted as an apprentice.
Now Hugo must work in the shop to make up for all the pieces he's stolen and Georges
will decide when he'll have done enough to earn the notebook back.
Georges teaches him all about clockwork inventions, toy making, and even a few magic tricks.
All this knowledge helps him fix the automaton, but to get it to function he still needs the
heart key.
In his free time, Hugo continues to watch Gustave catch kids and hangs out with Isabelle.
When she admits she's never seen a movie because Georges won't let her, Hugo takes her to the
theatre by sneaking through the back door, which he lockpicks with one of his tools.
The kids have a lot of fun with the movie, especially the part where a man hangs off
a big clock, but they're caught and kicked out before they reach the end.
On their way back to the station, Hugo tells Isabelle about all the movies Mr. Cabret would
take him to, like "A Trip to the Moon", which had a rocket landing on the Moon's face.
He also confesses he lives in the station walls.
Once they enter the station, Gustave stops them to check on Hugo, and Isabelle pretends
he's her dumb cousin from the country.
The dog is suspicious of Hugo's smell, but Isabelle comments it must be the smell of
her cat and Gustave lets them go.
Afterward, Isabelle asks to see Hugo's home in the walls, but he refuses and tries to
lose her in the crowd.
Unfortunately, Isabelle isn't used to crowds and almost gets trodded on, so Hugo comes
back to rescue her and discovers her necklace is the heart key.
Accepting to show Isabelle his secret, Hugo takes her to his room and borrows the key
to activate the automaton.
Fortunately, it does work, but the automaton only writes a few meaningless lines.
Hugo cries thinking he could've fixed it and wishing it could have a message from his father,
but suddenly, the automaton starts moving again and finishes its work: it's a drawing
of a scene from "A Trip to the Moon", signed by Georges Melies, which Isabelle identifies
as her godfather's full name.
The kids go to Isabelle's home to speak to Georges' wife Jeanne, telling her about the
automaton and showing her the drawing.
This upsets Jeanne, who asks them not to dig up the past because they're too young to understand.
At that moment, Georges comes back, so Jeanne hides the kids in her room.
There, Hugo looks for his notebook and notices that the wardrobe has a hidden compartment
with a box inside.
Since Isabelle is taller, she takes out the box by standing on a chair, but the chair
breaks and the box falls, revealing a bunch of beautiful illustrations that include "A
Trip to the Moon".
Georges hears this and comes to check on them, finding his work all over the floor.
This causes him to have a breakdown as he remembers he's nothing now but a penniless
merchant, he also calls Hugo cruel for breaking his trust like this.
Hugo returns to the station, where he bumps into Labisse carrying some books.
The man notices Hugo's interest in "Robin Hood le proscrit" because he used to read
it with his father, so Labisse decides to gift him the book since it seems it was intended
for him.
Meanwhile, Gustave tries to awkwardly make conversation with Lisette, but he's ashamed
of his leg, which never healed after a war incident.
Lisette doesn't judge him though, in fact, she reveals she lost her brother during the
war.
To show her sympathy, she gifts Gustave a couple of flowers.
The next day, Labisse tells Hugo and Isabell to go to the Film Academy library to find
the information they want.
A book called "The Invention of Dreams" reveals Georges was one of the first filmmakers and
very successful at his craft, having made over 500 movies, but it also says he died
during the Great War.
The kids' reading is interrupted by the book's author Rene, who is delighted to hear that
Georges is actually alive.
He takes them to see his private collection, explaining what a big fan of Georges he's
been since he was a little kid when he got to visit the set while his brother worked
there.
Nobody knows why Georges stopped making movies, but among his collection of memorabilia, Rene
has the only film of Georges' that has survived.
Later, Isabelle and Hugo discuss a plan idea while he maintains the clocks.
Hugo thinks everyone has a purpose, like machines, so maybe that's why Georges is sad all the
time: he lost his purpose and it's up to the kids to fix him.
Before leaving, Isabelle kisses Hugo on the cheek.
The next day, Hugo finds the heart key on the train rails and goes down there to recover
it, not noticing the train is arriving at the same time.
The locomotive operators aren't able to stop the train on time and the entire vehicle goes
off the rails, crashing against the station walls.
Hugo then wakes up, understanding it was all a dream, only to discover his body is becoming
an automaton, but this is a dream as well.
The following morning, for real this time, Claude's body is found in the river, and apparently,
he's been dead for a long while.
The authorities inform Gustave, who is now obsessed to find out who has been maintaining
the clocks.
Later in the evening, Hugo and Rene take Georges' last movie to his house.
Jeanne wants to kick them out before Georges sees them, but Rene recognizes her as one
of the actresses in Georges' movies and compliments her talents.
Overwhelmed by nostalgia and surprised there's still a film left, Jeanne decides to allow
them to play the movie in the living room while Georges sleeps.
The film turns out to be "A trip to the moon", which even has a few scenes in color.
Jeanne explains they tinted the film by painting each frame by hand.
Suddenly, Georges shows up in the room, having been woken up by the sound of his own movie
projector.
Jeanne points out that forgetting the past has only brought him unhappiness and now it's
time to remember, prompting Georges to finally share his story.
When he was young, he was a magician with Jeanne as his assistant; he was so successful
that he owned his own theatre.
He also liked tinkering with machines, and he had his own workshop in his theatre to
create new illusions, that was when he built the automaton.
When the Lumiere Brothers showed a movie for the first time, Georges was fascinated by
them and decided to build his own camera using leftover pieces from the automaton.
They decide to take the risk and sold the theatre to open their own movie studio, where
they made dreams come true.
Sadly, after many years of success, war came and forced him into bankruptcy.
One night, in bitter despair, Georges burned all the sets and costumes.
The movies were all sold to a company that melted them down into chemicals used to make
shoe heels, and the little money that left him was used to buy the toy shop.
The only thing he couldn't bring himself to destroy was the automaton, which he donated
to a museum hoping it would find a home.
Georges thinks the automaton burned down with the fire that killed Mr. Cabret and that happy
endings only happen in movies.
Wanting to prove him wrong, Hugo runs back to the station to grab the automaton, but
he stops on the way to overhear Gustave talking about Claude's death.
Unfortunately, a shopkeeper's dog comes to sniff Hugo and alerts Gustave of his presence,
causing Hugo to get caught and locked up in Gustave's office.
The inspector calls the orphanage to send Hugo there, explaining he went to one too,
where he was taught to follow orders and survive without a family because you don't need one.
While he's busy on the phone, Hugo lockpicks the cell door and runs away to hide in the
station walls.
In his hurry, he forgets to close the lid behind him, so when Gustave comes after him,
he manages to enter the walls as well.
In order to escape Gustave, Hugo decides to follow the movie he's seen with Isabelle and
climbs out of the building through the giant clock.
Gustave falls for the trick and thinks Hugo took another corridor, and once he's gone,
Hugo comes back in to retrieve the automaton.
On his way out, Gustave finds him again and causes him to drop the automaton on the rails,
so Hugo jumps in to get it back.
There's a train coming that can't be stopped, but luckily Gustave grabs Hugo and drags him
out of the rails.
The inspector still won't listen to Hugo's pleas and intends to take him to the orphanage,
but his plan is interrupted when Georges shows up and claims Hugo as his.
A few weeks later, Rene throws a gala to celebrate the life and work of Georges, who has been
named a professor at the Film Academy.
Thanks to a search through vaults, private collections, barns, and catacombs, they've
managed to recover some old negatives and decayed film, and now they have eighty of
Georges' films that they proceed to show.
During the afterparty, it's revealed that Gustave is dating Lisette and his leg now
has a much better clockwork-based brace made by Hugo, who is impressing all the guests
with some magic tricks.
Lastly, Isabelle has discovered her purpose is to be a writer, and she shall begin by
writing Hugo's story.