High school student David Lightman (Matthew Broderick) unwittingly hacks into a military supercomputer while searching for new video games. After starting a game of Global Thermonuclear War, Lightman leads the supercomputer to activate the nation’s nuclear arsenal in response to his simulated threat as the Soviet Union. Once the clueless hacker comes to his senses, Lightman, with help from his girlfriend (Ally Sheedy), must find a way to alert the authorities to stop the onset of World War III.
When talented computer engineer Kevin Flynn (Jeff Bridges) finds out that Ed Dillinger (David Warner), an executive at his company, has been stealing his work, he tries to hack into the system. However, Flynn is transported into the digital world, where he has to face off against Dillinger’s computerized likeness, Sark, and the imposing Master Control Program. Aided by Tron (Bruce Boxleitner) and Yori (Cindy Morgan), Flynn becomes a freedom fighter for the oppressed programs of the grid.
Teen misfits Gary (Anthony Michael Hall) and Wyatt (Ilan Mitchell-Smith) design their ideal woman on a computer, and a freak electrical accident brings her to life in the form of the lovely, superhuman Lisa (Kelly LeBrock). She outfits Gary and Wyatt in cool clothes, surprises them with a Porsche and helps them stand up to jerks Ian (Robert Downey Jr.) and Max (Robert Rusler). But, all the while, the boys must hide Lisa’s existence from Chet (Bill Paxton), Wyatt’s nightmare of a big brother.