We Have White Privilege?

In Highland, Texas, in 1998, Beavis and Butt-Head accidentally burn down their high school science fair. Believing them to be at-risk youth, a Judge sends them to space camp at the Johnson Space Center. Beavis and Butt-Head become engrossed in a docking simulator. Impressed, NASA astronaut Captain Serena Ryan invites them to train as astronauts, which they mistake as an offer for sex. They undergo training and board the Space Shuttle Endeavor to study a micro black hole.

In space, the boys create a catastrophe. When Serena volunteers to sacrifice herself, the boys mistake this for another offer of sex. Beavis and Butt-Head don their spacesuits and watch Serena through a window as she prepares to change. Enraged, Serena uses the shuttle controls to fling Beavis and Butt-Head into space, where they are sucked into the black hole.

Beavis and Butt-Head emerge in Galveston in 2022. The Pentagon detects their arrival and begins tracking them; Serena, now governor of Texas, vows to kill them to cover up her attempted murder. Beavis and Butt-Head meet intelligent versions of themselves from another universe, Smart Beavis and Smart Butt-Head, who explain that they have two days to enter a portal on top of Mt. Everest to prevent the destruction of the multiverse.

Beavis and Butt-Head acquire an iPhone and accidentally activate Siri, which they mistake for Serena; Beavis develops feelings for her. When Siri offers to set up their smart home, they believe Serena is waiting for them in Highland. After Beavis becomes trapped in a port-a-potty, he and Butt-Head are transported to a university. Smart Beavis and Smart Butt-Head urge them to enter the portal moved nearby, but instead they wander into a gender studies class, where the professor lectures them on white privilege. Taking this to mean they have the right to do whatever they want, they steal a police car and are arrested. In jail, Beavis takes pills given to him by an inmate, transforms into his hyperactive alter ego Cornholio, and incites an uprising. The warden discovers that the boys seemingly died in 1998. A fan of Touched by an Angel, the warden concludes that Beavis is an angel sent from heaven and releases them both.

The boys arrive home, expecting to find Serena, but find it has been placed for sale. They blame each other and separate, but are quickly abducted by government officials. Serena's downtrodden lieutenant, Hartson, covertly frees the boys, saying he knows what Serena did to them. Smart Beavis and Butt-Head urge them to enter the portal, but the boys ignore them.

All parties arrive at Beavis and Butt-Head's house. As Serena is about to shoot them, she realizes they are not her enemies, only foolish teenagers. Smart Beavis and Smart Butt-Head urge Beavis and Butt-Head to enter the portal, but Hartson is accidentally sucked in instead, closing the rift and saving the multiverse. As Beavis attempts to express his love to Serena, Smart Beavis interrupts and offers to show her the cosmos; she leaves with him and Smart Butt-Head. In exchange for their silence, the government gives Beavis and Butt-Head their home back in its original condition. In another universe, the assembled alternative Beavis and Butt-Heads applaud Smart Beavis for becoming the first Beavis to have sex.