Back in 1989, Sam Flynn's father disappeared. He was Kevin Flynn (Jeff Bridges), a computing genius who had pioneered huge advances in technology, but since Sam's mother had died he had lived with his grandparents, looking forward to the times when his father would visit. Now he wasn't going to visit anymore as any speculation - Kevin had become a recluse, he was dead, and so forth - came to nothing and Sam (Garrett Hedlund) grew up to be a deadbeat living on his father's fortune with little do about running the company that was Kevin's legacy...
If you can't work out where Kev has disappeared to, you obviously didn't see the first TRON movie, a box office failure back in 1982 that somehow won a cult following which grew to prompt Disney, always with an eye on the financial benefits of their products, to set up a sequel almost thirty years later. By that time the stars of the original were getting on a bit, which might explain why only two of them were invited back, Bridges and TRON himself, Bruce Boxleitner; that Cindy Morgan was nowhere to be seen rankled with many fans, although some missed the presence of David Warner (Cillian Murphy cameo'd in a sequel-baiting role as his character's son).
There may have been no sequel to Watcher in the Woods forthcoming, but that tricky period in Disney's live action endeavours did create cult movies, and TRON was the most significant, likely thanks to its computer preoccupation, an obsession with many an eighties science fiction flick. Although the plot itself was a curious mixture of Reaganite anti-Communism and demonstrating the perils of atheism, nobody much noticed that and preferred to be captivated by the pretty pictures, which under the design team of Steve Lisberger (who produced this follow-up) were among the most distinctive and accomplished of the decade. With director Joseph Kosinski on board, however, there were changes made.
Computer graphics had advanced in leaps and bounds since '82, which meant once Sam gets zapped into the land of the machine just as his father had been, the film looked similar but not identical to its initial incarnation. It might have been nice to see a retro appearance, but what they conjured up was very attractive nevertheless, with bright primary colours highlighted against deep blacks and greys, and indeed the best sequences were strongly reminiscent of Lisberger's work, light cycles, flying discs and what have you. What Sam finds is not that the scheming MCP has made a return, but that Flynn has an alter-ego, CLU (Bridges made to look younger courtesy of rather stiff CGI), who has taken over, and now has TRON as his righthand man.
This meant the anti-atheist theme was retained, only presented as a warning to any parts of humanity who get ideas above their station and wish to become all powerful, which isn't something you can do in real life, but is something you can do in the conceit of the computer world. CLU is now the supreme being of that, proof of the arrogance of not only the program but of Flynn too, and the man himself has paid a humiliating price, an exile living with his assistant Quorra (Olivia Wilde) who is convenient girlfriend material for his son, what with her action heroine status. In addition, there was a warning to the illegal downloaders of Planet Earth who wanted everything online for free: that way lies anarchy, TRON Legacy tells us, typified by the way the dangerous CLU and his minions want to access the entirety of the internet as they please. But you didn't need to worry about that when you could soak in the state of the art graphics, Daft Punk's sleek electro-orchestral score, and wonder what Michael Sheen was thinking in his portrayal of a louche yet crazed baddie.