When kids slot a coin into the Fix-It Felix arcade machine, they get the chance to control the titular hero (Jack McBrayer), a jaunty do-gooder who uses a magical hammer to fix the destruction to an apartment block caused by his heavy-handed nemesis Wreck-It Ralph (Reilly).
But when the kids go home and the Arcade shuts down for the evening, the video game characters get to clock off and enjoy some down time. Unfortunately, given his villainous status (and stature), Ralph is ignored by his cohorts in the apartment block and left in a dump full of bricks, night after night.
Attending the villain support group 'Bad Anon' with the likes of Mario nemesis Bowser and the ghosts from Pac Man doesn't quite help, and Ralph, after years of service, decides he wants to play the good guy. By doing the unheard of - switching games.
Unfortunately, his brief trip to a sci-fi shooter, where he comes across Jane Lynch's hard-as-nails military type Calhoun, followed by a sojourn into kiddie friendly Sugar Rush, a Mario Kart-like game full of bright colours and candy coated cars, was not a good idea.
Inadvertently bringing certain doom with him, Ralph's too interested in becoming a hero to realise he's about to destroy the entire arcade.
But as trouble brews, literally under the surface, Ralph finds himself stuck in Sugar Rush with a sweet but dodgily programmed poppet called Vanellope von Schweetz (Sarah Silverman), whose glitchiness saw her booted out of the Sugar Rush races.
There's more to her outsider status than meets the eye, and Ralph soon realises that helping the kid achieve her racing dream is the path to true heroism…
There are plenty of kids' cartoons, Disney, Pixar or otherwise that explore the 'what happens when humans are not looking' premise, but few, with the exception of Toy Story, come close to Wreck-It Ralph's eye for detail.
Yet for all the witty asides and genius references (a standout moment features Street Fighter II's Ken supping beer in the background as he enjoys some down time from punching Ryu) would be for nothing but for Wreck-It Ralph's plot.
It's the kind of story that, like Back to The Future, could be used to teach film students how to set up and pay off. All threads are not only tied, but tied to each other. Pixar would - and will - be proud of it, thanks to the involvement of Toy Story director John Lasseter as producer.
Most notably, the characters are multi-dimensional, a hugely pleasant surprise for a movie based on pure storytelling. Felix is not the self-regarding goody-two-shoes he first appears to be. He's a genuine good guy, electing to risk his life to save Ralph, and the arcade, from destruction.
Wreck-It Ralph is a joy to watch. Possibly the only movie released this year to be based on a videogame that's fresh and original. Put a coin in the slot and sit back and enjoy; it's the best Pixar movie the studio didn't make, and there can be no higher praise.