Robots

In a world of robots, Rodney Copperbottom, son of Herb and Lydia Copperbottom, is an aspiring young inventor from the city of Rivet Town. He idolizes Bigweld, a famous inventor and philanthropist whose company, Bigweld Industries, employs other inventors and provides poor robots with spare parts. Rodney develops the diminutive Wonderbot to assist his father, who works as a dishwasher in a restaurant. When Herb's boss, Mr. Gunk, confronts them, however, Wonderbot malfunctions and wreaks havoc in the kitchen.
To help Herb pay for the damages, Rodney travels to Robot City, hoping to present Wonderbot to Bigweld Industries. However, upon his arrival, Rodney is ejected from Bigweld Industries by its new CEO, Phineas T. Ratchet. In Bigweld's absence, Ratchet has discontinued production of spare parts and inventions for the poor outmoded robots, prioritizing expensive "upgrades". Meanwhile, Ratchet's mother Madame Gasket runs the Chop Shop, a facility that recycles scrap metal collected by her Sweepers, including that of deceased or outmoded robots, into ingots for upgrades.
Rodney befriends Fender Pinwheeler, a ne'er-do-well who introduces him to a group of outmoded robots known as the "Rusties". Rodney and his new friends help to fix outmodes throughout the neighborhood, but they are eventually unable to cope with the demand due to the spare part shortage. Hoping to enlist Bigweld's help, Rodney and Fender infiltrate the Bigweld Ball, but Ratchet announces that Bigweld will not attend. An enraged Rodney confronts Ratchet, who orders his security team to eliminate him. Cappy, an executive opposed to Ratchet, rescues Rodney and Fender. While Fender is captured and taken to the Chop Shop by a Sweeper, he discovers their plan to scrap all outmoded robots with new machines designed to destroy them.
Rodney and Cappy fly to Bigweld's mansion, where he lives as a recluse and reveals that Ratchet's greed led to his resignation and refuses to help them. A distraught Rodney calls his parents, but Herb inspires him to fight for his dreams. Fender escapes the Chop Shop and exposes Ratchet's plot. Rodney rallies the Rusties, and Bigweld, reinvigorated by Rodney's spirit, joins them to stop Ratchet. Rodney and his friends return to Bigweld Industries where Ratchet attempts to dispose of Bigweld, who ends up being rolled into the Chop Shop. Rodney upgrades the Rusties and leads them in a battle against Ratchet, Gasket, and their army of workers and Sweepers. Gasket is eventually flung into the incinerator and destroyed, and Ratchet is stripped of his upgrades and left chained with his father.
Retaking control of Bigweld Industries, Bigweld holds a public ceremony in Rivet Town, where he nominates Rodney as his new second-in-command and eventual successor. Rodney provides Herb with new replacement parts and a flugelhorn-like instrument to fulfill his life-long dream of being a musician. Herb leads the townspeople in a rendition of "Get Up Offa That Thing".