"Saw" is the story of David (Leigh Whannell), an orderly at a hospital who is explaining to a Cop (Paul Moder) the story of how he ended up involved in a heinous crime against his will. One day after work, David gets kidnapped by a mysterious man who drugs him and takes him to an unknown location. When he wakes up, David is sitting on a chair in a darkened room, and has a bizarre artifact placed over his head. In a TV screen he sees an odd looking ventriloquist's dummy, who informs him (obviously the voice is the one of his captor) that the device is a "Jaw Splitter", a machine that will crush his skull if he can't stop it on time. The key to David's survival is to find the key that stops the Jaw Splitter, a key that the killer informs him is hidden inside the body of the dead man lying in the same room as David. But when David goes to get the key, he discovers horrified that the man he has to open is not dead.
Written by actor Leigh Whannell, "Saw" has all the core elements of the "Saw" series premise: a serial killer who do not kills with his own hands, but who instead puts his victims in a deadly trap where they have a chance (albeit small) of survival by doing an often difficult and painful (either physically, mentally or emotionally). It's an interesting take on horror that returns elements of suspense to the genre, as the shock is not only in the killing itself, but in the tension caused by the events that lead to it, and in the idea that the characters can escape from their dreadful fate. It's certainly a simple story, but despite this the concept feels truly fresh and original thanks to this focus. As many will notice (specially fans of the series), "Saw" the short film eventually became part of the first "Saw" film, as it evolved into the experience Amanda has with Jigsaw.
Just as the screenplay has most of the elements that became core part of the "Saw" series, James Wan's work as a director already shows where he was going with this concept and what exactly he wanted to do with it. Like the "Saw" films, the visual look of the short film is sleek, but with a welcomed touch of grittiness that fits perfectly the concept of brutal torture devices of the modern era. The highly dynamic camera-work that Wan uses later in "Saw" is also here (courtesy of cinematographer Martin Smith), as well as his preference for industrial metal music as soundtrack. However, while this was only a low-budget short film, this style feels more at home here than in the feature movie (where it gets tiring), as the atmosphere of fear, shock and desperation it's supposed to create works better in the short than in the films (no wonder why this scene in the feature film is the most iconic).
The acting is also better in this short than in the scene from the feature film, with Leigh Whannell giving a solid and very realistic performance as David. One can truly feel that his character has gone through hell and back, specially in his scenes with the Cop. Please not that I'm not saying that Shawnee Smith (who plays Amanda in the feature) is a bad actress, I'm just saying that Leigh Whannell seems to put a lot more of effort in the role than her (without a doubt because this was his pet project). However, that also must have something to do with the fact that in the feature, Amanda is just another victim, while here, the tortured character is also our narrator, so that gives Whannell more room to explore the role. By the way, Whannell's character is different to the one he plays in the feature, although one is certainly the evolution of the other.
Personally, I found "Saw" the short to be a lot better than "Saw" the film, mainly on the basis that it has everything that makes the first film in the series great (the fresh, original approach to horror and its creative story) without the elements that in my opinion work against it (it obviously lacks the underdeveloped subplots that lead to nowhere in the film). As it was done with a low budget, Wan and Whannell had to use creativity to make it work, and the result is wonderful, as while it may lacks the more graphic violence of the feature (due to the already mentioned budget constrains), it plays more with suspense and tension, which make it a bit more atmospheric and haunting than the movie gets to be. "Saw", the short film, is a very interesting movie to watch (and not only for fans of the series), as it shows what one can do when one plays with an idea and lets it grow.