With anticipation high and climbing with each image and trailer for the release of Tron Legacy (and it ranked first on our round-up of films to look forward to in the link below), the next best thing to do before the film is out was to have another look at the 1982 film, which was just as exciting on its release 28 years ago.

Since we had the Collector's Edition on our shelves, we actually made two return trips to a film that pioneered filmmaking techniques because what the filmmakers wanted to accomplish had never been attempted before.

We were quite surprised to learn that most of the effects, which we'd ashamedly assumed were computer-generated accomplishments, were actually painstakingly hand-drawn animations, in a process that, even having heard how it was done, we still don't quite understand!

Our second spin through the film with the commentary track also confirmed for us a couple of facts, with some extra details we weren't yet aware of. For instance, if, like us, you were sure you saw a rudimentary face in the Recognizers that appear throughout the film, you'd be absolutely correct, as the filmmakers reveal that was always the intention.

In fact, the Recognisers that police the electronic world were intended to be "sort of a King Kong" shape, with "a suggestion of a face" above the gate structure.

Although they were a bit less than satisfied with the implementation, believing the King Kong face "got lost", we're sure that giving a name to the face will imbue the Recognizers with their full weight and threat on future viewings and it's hard not to forever envision a futuristic fleet of Kongs patrolling the Tronscape.

The second sighting, we're both ashamed and shocked to admit, was something we'd never spotted in any of our Tron viewing sessions during the twenty-eight intervening years between its hitting the big screens and our private viewings in our own living rooms.

As Tron, Flynn and Yori travel on the solar sailer, they pass over a mountainous terrain that also takes them by a lake. A digital lake shaped exactly like the head of Disney's Mickey Mouse. It's a fleeting moment in chapter 14 at 1:09:28. Still, we're astounded that we failed to spot it without the help of the commentary track.

The last spotting was without the aid of the secondary audio track and is one we got the biggest geek goosebumps from, and one that, coincidentally, is very well timed.

David Warner (as yet another British bad guy in a cast of American actors) took on the dual roles of Ed Dillinger and Sark and also provided the voice of the evil English-accented Master Control Program, with some digital effects applied.

In chapter 9 at 0:43:30, as Sark barks orders to an underling, to his right is Pac-Man, frantically munching away in vain, with a trail of pac-dots visible but beyond the little guy's reach. And if there's any doubt of the full investment in his guest starring role, you can hear the familiar sounds of the game just below the dialogue.

It's surprising that there's no mention of the Pac-Man appearance on the commentary track and, viewing it with that audio playing, you don't hear the game's recognisable sound, making it easier to miss. Even more noteworthy is the appearance in the context of the timing of the film and game's release.

Namco's Pac-Man had debuted in Japan two years before the July 1982 US theatrical release of Tron, a film we'd guess took a fair bit of advance preparation and work to complete. (Just a couple months later, in September 1982, "Pac-Man", the animated television series produced by Hanna Barbera, debuted on stateside tellies, running until November 1983.)

The filmmakers' cheeky inclusion of a short, but amazingly fun tribute to what they somehow guessed correctly would become an iconic mascot of the game-playing audience, and not a dated reference to long forgotten trivia, commonplace cultural reference or trifling product placement, is another notch in the geek belt of a terrific film and is, perhaps, even more of a find now, with the realisation that the film and the game are still well loved today, while fast approaching three decades of existence.

Will Tron Legacy include any surprises beyond the magnificent scenes we've seen in the trailers? We'll have to wait until December to find out. But, if it took us this long to spot a gigantic Mickey Mouse head in numerous viewings, we're prepared to watch and rewatch Tron Legacy, on the off chance we may have missed something.

We can certainly think of worse ways to spend our time.

• 10 films to look forward to this autumn
• TRON revisited
• Brand new trailer for Tron Legacy

A larger version of the Pac-Man image is below. Click to have a bigger, better look.