At a video game arcade in 1982 with his friend Will Cooper, Sam Brenner discovers he can master the games by spotting patterns. Participating in a video game championship, he loses to Eddie "the Fireblaster" Plant in Donkey Kong. A videocassette with footage of the event is included in a time capsule that is launched into space. In the present day, Brenner has become an installer of home-theater systems while Cooper is the disliked President of the United States. In Guam, a U.S. military base is besieged by an extraterrestrial force attacking in the form of the video game Galaga and a soldier is abducted.
Brenner works at the home of divorcée and U.S. Army Lieutenant Colonel Violet van Patten, but the two are separately summoned to the White House. Upon seeing the video footage and meeting with Ludlow "the Wonder Kid" Lamonsoff, a friend he and Cooper made at the video game championship, Brenner determines that an alien race has misinterpreted the videocassette images as a declaration of war and are attacking with technology based on the games featured at the championship. This is affirmed when the aliens interrupt a television broadcast using manipulated footage from the cassette, challenging Earth to a battle where if the aliens win three rounds, they will conquer the planet. Brenner and Cooper are unable to stop one of the attacks as several aliens taking the form of the Vaus from Arkanoid are used to destroy the Taj Mahal, and a bystander is abducted.
Violet showcases newly-developed rayguns that are effective against the aliens as Brenner and Ludlow train Navy SEALs to play the games. In London, the aliens attack Hyde Park in the form of Centipede, but as the soldiers are unable to defeat the creatures, Brenner and Ludlow step in. Following the victory, the aliens send a congratulatory message to the team and a "trophy" in the form of an alien taking the form of the dog from Duck Hunt to an old woman who appeared earlier at the London attack.
Ludlow and Cooper retrieve Eddie, who had been serving a prison sentence for fraud. In New York City, the team learns that an alien taking the form of Pac-Man is on a rampage. Brenner, Ludlow, and Eddie are given four modified Mini Cooper cars to use as the ghosts from the Pac-Man series, with the fourth one being piloted by Pac-Man creator Toru Iwatani. When the group confronts the Pac-Man alien, Iwatani tries to reason with it peacefully, but he gets his hand bitten off and flees. The remaining three then overcome the task, but Violet notices that something about Eddie is off, as he moved at supersonic speeds around the board. They win an alien taking the form of Q*bert as a trophy. Later during a celebratory party however, the aliens send a message declaring that someone cheated and the challenge for the planet has been forfeited. Violet's son, Matty, discovers Eddie is the perpetrator, having used a speed cheat during the battle against Pac-Man. Eddie flees while Matty is abducted by the aliens.
The aliens launch a massive attack using an army of aliens taking the forms of various characters and enemies from the championship's games in Washington, D.C.. Cooper joins the team, while Ludlow stays to fight. An alien takes the form of Lady Lisa, a character who Ludlow had a crush since childhood. Ludlow persuades Lisa to choose love, and she sides with the humans; Eddie, wishing to make amends, returns to fight as well. Brenner, Violet, Cooper, and Q*bert are summoned to the aliens' mothership where they face the alien leader who takes the form of Donkey Kong on the game's starting level with the aliens' captives at the top. As the group dodges the obstacles, Brenner begins to lose hope, until Matty reveals Eddie's cheating to him, thus restoring his confidence and allowing him to defeat Donkey Kong. This causes the aliens' forces to self-destruct, including Lisa.
The team is hailed as heroes and a peace agreement is reached with the aliens. Eddie apologizes to Brenner for his cheating, and although Ludlow is saddened that Lisa is gone, his spirits are lifted when Q*bert transforms his likeness to her. Brenner and Violet become a couple while Eddie gets to meet Serena Williams and Martha Stewart. The aliens reverse all the destruction they caused before they depart, even restoring Iwatani's hand. One year later, Ludlow and Lisa are married and have Q*Bert-like children.
Adam Sandler as Sam Brenner
Anthony Ippolito as 13-year-old Brenner
Kevin James as Will "Chewie" Cooper
Jared Riley as 13-year-old Cooper
Michelle Monaghan as Lieutenant Colonel Violet von Patten
Peter Dinklage as Eddie "The Fire Blaster" Plant
Andrew Bambridge as 13-year-old Eddie
Josh Gad as Ludlow "The Wonder Kid" Lamonsoff
Jacob Shinder as 8-year-old Ludlow
Brian Cox as Admiral James Porter
Sean Bean as Corporal Hill
Jane Krakowski as First Lady Jane Cooper
Affion Crockett as Sergeant Dylan Cohan
Ashley Benson as Lady Lisa,
Matt Lintz as Matty van Patten
Lainie Kazan as Mickey Lamonsoff
Dan Aykroyd plays the emcee of the video game championship. Nick Swardson plays a bystander seen in the Pac-Man attack. Dan Patrick, Robert Smigel and Steve Koren play White House reporters. Celebrities Serena Williams and Martha Stewart have cameo roles as themselves. Matt Frewer reprises his role as Max Headroom, a role he made famous during the 1980s. Steve Wiebe, a previous Donkey Kong and Donkey Kong Jr. World Record holder, plays a military scientist. Denis Akiyama portrays Toru Iwatani, the creator of Pac-Man, while the real Iwatani has a cameo role as an arcade repairman. Fiona Shaw plays the Prime Minister of the United Kingdom.
Additionally, various celebrities who were popular in the 1980s, including Ricardo Montalbán, Hervé Villechaize, Tammy Faye Bakker, Madonna, President Ronald Reagan and the band Hall & Oates, are shown via archival footage.
Tom McCarthy played Michael the Robot, while screenwriter Tim Herlihy played a Defense Secretary. Sandler's wife Jackie played President's Assistant Jennifer, while their children appear elsewhere in the film: Sadie plays Cooper's sister at the lemonade stand, and Sunny plays a Scout Girl. Jared, Sandler's nephew, plays a White House Junior Aide, Producer Allen Covert plays an abusive citizen, while his kids Hannah and Abigail plays an Arcader Choir Girl and another Classroom Scout Girl. Kevin James's children Sienna and Shea Joelle play other Classroom Scout Girls.
A feature-length adaptation of French director Patrick Jean's 2010 short film of the same name