The Plot:
Inventor Frank Walker addresses an unseen audience about the future. When he was a young boy, Frank attended the 1964 New York World’s Fair, to sell his prototype jetpack.
It is rejected by judge David Nix on the basis that it doesn't work. Frank is approached by a young girl, Athena, who hands him a blue lapel pin with an orange “T” embossed on it, telling him to follow her onto Walt Disney's “It's a Small World” attraction at the Fair's Pepsi-Cola Pavilion.
Frank obeys and sneaks onto the ride, where the pin is scanned by a laser, and he is transported to Tomorrowland, a futuristic cityscape, where advanced robots fix his jetpack, allowing him to fly and join the secretive world.
Frank passes the narration to the optimistic teenager Casey Newton. In the present, Casey repeatedly sabotages the planned demolition of a NASA launch site in Florida.
Her father, Eddie, is a NASA engineer, but faces losing his job. Casey is eventually caught and arrested. At the police station, she finds a pin in her belongings (which appears similar to the pin young Frank was given by Athena, but colored oppositely).
While touching it, the pin transports her to Tomorrowland. Her adventure is cut short when the pin's battery runs out, frustrating her.
With help from her younger brother Nate, Casey finds a Houston memorabilia store related to the pin.
The owners, Hugo Gernsback and his wife Ursula, attack her when she is unable to divulge where she got the pin, insisting that Casey knows about a "little girl." Athena, who gave Casey the pin, bursts in and defeats the owners, actually Audio-Animatronics, who self-destruct, blowing apart the shop.
After Casey and Athena steal a car, Athena reveals she is an animatronic, purposed to find and recruit people who fit the ideals of Tomorrowland. Athena drops Casey off outside an adult Frank’s house in Pittsfield, New York.
The reclusive, cynical Frank declines Casey’s request to take her to Tomorrowland, having been banished from it years ago. Inside Frank’s house, Casey finds a probability counter marking the end of the world.
Frank warns her that the future is doomed, but she disagrees, thus lowering the counter’s probability. Animatronic assassins arrive to kill Casey, but she and Frank escape, meeting Athena in the woods outside Frank's house. Frank resents Athena for lying to him about her true nature, but reluctantly agrees to help them get to Tomorrowland.
Using a teleportation device, the trio travel to the top of the Eiffel Tower. Frank explains that Gustave Eiffel, Jules Verne, Nikola Tesla, and Thomas Edison co-founded Plus Ultra, a secret society of futurists, creating Tomorrowland in another dimension, free to make scientific breakthroughs without obstruction.
The trio use an antique rocket hidden beneath the Eiffel Tower – called the Spectacle – to travel to Tomorrowland.
There, they find Tomorrowland in a state of decay. David Nix, now Tomorrowland’s governor, greets them.
They travel to a tachyon machine, invented by Frank, which accurately predicted the worldwide catastrophe. Casey refuses to accept the world will end, causing the future to temporarily alter. While Frank attempts to convince David to listen, he refuses and intends to have the group leave Tomorrowland.
Casey realizes the tachyon machine is telling humanity that the world will end, creating a self-fulfilling prophecy.
They confront David, who admits he tried to prevent the future by projecting such images to humanity as a warning.
Instead, they embraced the apocalypse, refusing to act to make a better future for their world. Believing that humanity simply gave up, David has also given up and intends to allow the apocalypse to happen. Casey, Frank, and Athena attempt to use a bomb to destroy the machine, leading to a fight with David.
The bomb is accidentally thrown through a portal to an uninhabited island on Earth, the explosion pinning David’s leg. Athena sees a vision of the future where Frank is shot by David, and she jumps in the way of his attack, mortally wounding herself. Making peace with Frank, Athena activates her self-destruct sequence, destroying the machine which falls on David, killing him.
In the present, Casey and Frank lead Tomorrowland, recruit Eddie and Nate, and create a new group of recruitment animatronics like Athena, whom they were addressing at the beginning of the film. Given pins, the animatronic children set out to recruit new dreamers and thinkers for Tomorrowland.
