The film picks up directly after the events of the previous film. The Incredibles and Frozone battle The Underminer and successfully prevent him from destroying City Hall, but are unable to stop him from robbing a bank and escaping. The collateral damage gives the jealous government the perfect excuse to shut down the Superhero Relocation Program, denying the Parrs and other superheroes financial assistance. Violet’s love interest Tony Rydinger discovers her superhero identity, causing agent Rick Dicker to erase his memory of her.
Wealthy businessman Winston Deavor and his sister Evelyn, who run the media and telecommunications giant DevTech, propose secret missions for superheroes which will be recorded and publicized to regain public trust. Winston chooses the less accident prone Elastigirl over Mr. Incredible for the initial missions.
Bob struggles in his new role as a stay-at-home parent: trying to help Dash with math homework, Violet’s heartache over Tony standing her up for their first date (due to his memory wipe), and Jack-Jack wreaking havoc with his burgeoning superpowers. Edna Mode develops a suit to help control Jack-Jack’s abilities. Meanwhile, Elastigirl encounters supervillain “the Screenslaver”, who projects hypnotic images via TV screens. After preventing him from destroying a crowded commuter train, and thwarting his attempt to assassinate an ambassador, she tracks him to an apartment building and unmasks him as a pizza deliveryman who claims to have no recollection of his actions.
At a party celebrating the Screenslaver’s arrest, Winston announces a summit of world leaders to legalize superheroes, hosted aboard his luxury yacht, the Everjust. Elastigirl discovers that the arrested pizza deliveryman is not Screenslaver but was being controlled by hypnotic goggles.
Evelyn forces the goggles onto Elastigirl, revealing herself to be the Screenslaver. While keeping her restrained via a chair in a freezing cold room to limit her stretching abilities, Evelyn explains her grudge against superheroes since her father was killed by burglars while trying to call superheroes for help instead of hiding (unlike Winston who rightfully believed the lack of superheroes was the reason) and her mother’s subsequent death due to heartache.