Welcome to the OASIS, a hyper-realistic, 3D, videogame paradise. It's 2045, and pretty much everyone logs in to the OASIS daily to escape their terrible lives, lives affected by overpopulation, unemployment, and energy shortages. Eighteen-year-old Wade Watts is one of these people, and he has a mission: to find an Easter egg hidden inside the OASIS by its wackadoodle creator, James Halliday.
In order to get to the egg, a player must first find three keys and unlock three gates. Wade—playing as his avatar, Parzival—finds the first key, the Copper Key, inside the Tomb of Horrors. There he also meets Art3mis, a young blogger with a sexy, shapely avatar that catches Wade's eye. Ooh-la-la the flirtmance begins.
Wade handily unlocks the First Gate by re-enacting the entire movie WarGames. He gets a hint to the location of the Jade Key, but it's a doozy. While he tries to decipher it, he and Art3mis go on a variety of digital dates. Their relationship comes between Wade and his best friend, Aech, and they start to drift apart. Art3mis soon cuts off communication with Wade, too, because she wants to focus on winning the big prize.
While trying to find the Jade Key, Wade investigates the planet Archaide. There, he plays a perfect game of Pac-Man and wins a quarter. Not even a real quarter—it's an item for his inventory, and it doesn't appear to have any practical use whatsoever. Gee, thanks.
Art3mis finds the Jade Key first, followed by Aech, the samurai Daito and Shoto, and the Sixers, employees of IOI, an Internet Service Provider putting all its resources into finding the egg so that they can control the OASIS. Things are getting dicey. Aech gives Wade a clue to the key's location, sending him to the planet Frobozz, a recreation of the classic computer game Zork. Wade gets the key no problem, and proceeds to unlock the Second Gate and grab the Crystal Key with little effort, heading through worlds that re-enact Blade Runner, the game Black Tiger, and the Rush album.
But there's a problem: the Sixers already have the Crystal Key. The good news is that they have no clue how to unlock the Third Gate, so the game ain't over yet. Thanks to their knowledge of Schoolhouse Rock! Wade and the gang know how to unlock the Gate: they need the power of three.
After an epic giant robot versus Mechagodzilla battle, Parzival, Aech, and Art3mis unlock the Third Gate just as the Sixers set off the Cataclyst, killing everyone instantly. Thankfully, the quarter Wade received after his perfect game of Pac-Man serves as an extra life. Parzival survives. He enters the final gate, triumphs over its challenges—a game of Tempest followed by a recreation of Monty Python and the Holy Grail—and finds himself in Halliday's office. There, he meets Anorak, Halliday's avatar, and is awarded digital immortality and Halliday's billions of dollars in assets. Bonus!
Back in the real world, Wade meets Art3mis (for real) for the first time. She's as beautiful as he had imagined. He tells her he loves her (she doesn't respond in kind, but he doesn't notice), and together they ponder what to do with their newfound fortune. An eternity of leisure and videogames, or world peace? Tough call.