Kevin Flynn, a video game programmer, suspects foul play when his former business partner, Ed Dillinger, steals his ideas and becomes successful. While illegally trying to access his old workplace to retrieve evidence of the theft, Kevin is mysteriously transported into the digital realm of the mainframe computer system.
Inside this virtual world, Kevin encounters various programs, including Tron, a security program and gladiator. Tron informs Kevin that the Master Control Program (MCP) has taken over the computer system with an iron grip and considers Kevin a threat. MCP organizes competitions called "games" where programs fight for their freedom.
Kevin teams up with Tron to challenge the MCP's oppressive regime. They face several trials, including light cycle races, disc battles, and encounters with deadly opponents. Along the way, Kevin befriends other programs like Yori and Dumont.
As Kevin navigates the digital landscape and gains a better understanding of the virtual world, he realizes that he must not only confront the malevolent MCP but also find a way to return to the real world. Throughout the adventure, Kevin learns valuable lessons about friendship, trust, and the consequences of unfettered power.
The film raises thought-provoking questions about the interactions between humans and technology and the ethics of artificial intelligence. It incorporates innovative visual effects, including computer-generated imagery (CGI), that were groundbreaking at the time of its release.