Matthew Broderick plays David Lightman, a bored, tech-savvy high schooler who thinks he's hacked into a video game company to play an unreleased game, only to discover he's actually accessed WOPR, a Department of Defense supercomputer, and inadvertently started a countdown toward real nuclear war. Director John Badham builds tension from the terrifying possibility that a machine designed to simulate war games might not understand the difference between simulation and reality. Released at the height of Cold War anxieties, the film became a genuine cultural phenomenon, credited with popularizing hacker culture in mainstream media and reportedly influencing President Reagan's early thinking on cybersecurity policy. Its closing lesson, delivered by the AI itself, remains one of the most quoted lines in techno-thriller history.