I want to get one thing out the way up front: I have not seen all of the Saw films. I have seen the first three. I started watching the fourth before switching it off from disinterest. I am aware that it is considered (rightly so) bad form to criticize something you haven't seen, but I've tried to follow the ongoing story via Wikipedia summaries. Honestly, I'd argue based on 2 & 3 (and what little I saw of 4), actually watching the films after a certain point might not be necessary.
So yes, I have come to bury the Saw films, not to praise them.
Which is too bad, because I thought the first one was flawed, but generally pretty cool. It was atypical for North American horror films at the time. There was a tension between the simplicity of the situation in which the two main protagonists found themselves and the baroque storyline of betrayal and intertwined relationships surrounding them. The visual aesthetic was equally tense, contrasting grimy, believably decayed locations with the almost operatic quality of the killer's traps and methods. Sort of a locked-room murder mystery by way of Dario Argento, set in an abandoned, rusting warehouse. It definitely had its flaws - it was shot without rehearsal and showed, and enough scenery got chewed toward the end that I worried about the actors getting tetanus. But as a singular story, it had promise, and it was something a little new and different.
New and different isn't always a guaranteed good thing, but in this instance it paid off. In terms of the business of filmmaking, this was great - a couple of relative unknowns, with not that much of a budget, turned out a successful horror film that wasn't just another smirky, ironic riff on the slasher film. Any time deviation from the tried and true pays off, it makes it a little easier to get some new blood more opportunities, and that's good. In terms of the art of filmmaking, this was also great - it was both grittier and more stylized than most commercial North American horror films to date, and so it added a lot to the potential visual vocabulary of horror film. Even the ad campaign had a little something to it - the posters for Saw looked like something Joel-Peter Witkin might do.
The problem comes in when art and business meet. Saw was commercially successful, and as a commercial product, its underwriters wanted to replicate its success. Fair enough, that's business. They paid for production, they got a return on investment, they'd like to keep going with a successful product. If you want to argue artistic purity, commercial film production is the wrong place to do it. However, films - however much a product they are - are still received, understood, and consumed as art (or entertainment). So in that sense, they can and should be evaluated on those terms, regardless of the place they occupy on a spreadsheet.
I am going to argue that the "franchising" of horror films is a bad thing, using the Saw films as a case study. In specific, the power of a film as a synthesized whole is diluted by increasing emphasis on its parts, and the power of the story, as originally conceived, is muted by and buried under increasingly complicated additions to the original narrative for the sake of maintaining some sort of franchise continuity. In general, this process not only makes individual films less effective as horror films, but shifts emphasis from creating art to laying the foundations for product.
In my opinion, much of the power of horror film lies in mystery. The unknown is a big part of horror film, however it shows up - the protagonists don't know how they got where they are, they don't know where somebody went, they don't know who is stalking them, they don't know why the bad things are happening to them, they don't know what type of creature is attacking them. The audience doesn't know these things either, or they do know when the protagonists don't and they get freaked out because they know the protagonists are in danger when they don't. Or the protagonists know something the audience doesn't and does something the audience doesn't understand and won't until all is revealed. The unknown scares us, and having the unknown become known also scares us (the power of the twist). In Saw, we spend the movie finding out why the two men are where they are and what brought them there and what's going to happen to them, and those are the sort of things that scare us.
In a sequel, then, you're already starting at a disadvantage just by virtue of there being less mystery. We've seen the monster in the first one, whatever the monster is. Now it is a known quantity. Whether it's the monster's identity, its motivation, its methodology, whatever, now we know something about that, so it doesn't scare us as much. By the end of Saw, we know that the Jigsaw Killer is a terminally ill man who resents the way others squander life, so he puts people into situations which force them to reexamine themselves and their fears, leading to a greater appreciation for the life they have. So we're already prepared for that going in. There's no threat left in that information.
So then what of the original film is left? We have a pretty good idea of what happened to the two original protagonists (nothing good), and the supporting cast is either dead or of little consequence. As far as we know, their story is over. What we have left are Jigsaw's traps, or "games", as he calls them.
(In my world, Jigsaw relies more on things like the Prisoner's Dilemma and less on rusty bear traps. But I'm a nerd.)
The traps are pretty much the engine driving the sequels. They're going to evoke a response (shock, revulsion) every time, and knowing they're coming isn't a disadvantage, it's a selling point. It's what separates the Saw films from other slasher films, which themselves rely on increasingly gruesome or baroque "kills" (scenes in which people are murdered) to keep audiences coming in for the sequels. I'd argue that these scenes of violence, largely devoid of context or character development, are the fats and sugars of our horror movie metabolism. A little is great - sudden bursts of violence can be very effective as a dramatic tool - but too much at the expense of story or pace or mood or character just leaves you empty, less scared than jolted and disgusted. (Yes, I just compared some horror movies to fast food. That was weak. But stick with me.)
So the appeal of the Saw sequels - since we now know who is behind these atrocities and why - is the sensations the traps evoke. They're the "kills" to which the audience is going to react. If you're going to make a successful Saw movie, then, you need to pay close attention to how you write the trap scenes. The traps need to be good, because it's the traps that are going to bring people into the theaters once all of the other mysteries are gone. There's also an element of one-upmanship, because each set of trap sequences you design are going to accustom the audience to a particular level or type of gruesomeness. So the next set needs to be "worse", somehow, to get the same feeling from the audience. This is true of pretty much any stimulus - it's a habituation effect. Pain is bad, suffering is worse, suffering of the innocent is even worse. Spikes are bad, blades are worse, needles are even worse, drowning in rotten pig entrails is yet again worse. And so it goes.
The more attention goes into the traps (since that's the feature attraction), the less goes into things like setting, mood, and characterization. These are less important because it doesn't matter who is going up against Jigsaw or where - we already know all about Jigsaw. There's no mystery there. The only mystery left is what the traps are going to be and who will be killed in which order. There may be some pretext to get all of the victims in place (Jigsaw's "game" with the police officer in Saw II involved his son and a number of people who fell afoul of his cavalier police methods), but we aren't going to find out anything about these people outside of their rationale for being there, because their only dramatic purpose is as models for the elaborate traps which are the constant of the series. The characters in any given Saw film after the first are either Jigsaw, an audience for Jigsaw, or cannon fodder.
Which is not to say that every horror film needs to be a character study, but if we're not going to care about the characters as people, then the situation in which they find themselves should be pretty evocative. We should at least sympathize with the characters just enough to not want to see them hurt or dead, just enough for the evocative situation to make us feel something. In the Saw films, it's a pretty one-way street. There are traps, and people are going to die in them, sooner or later. It's the difference between moving chess pieces around a board and feeding meat into a grinder. One engages us as viewers, asks us to anticipate moves, allows us to recognize the implications of events and feel something as a result of our discovery. The other is tedious inevitability. Oh, look, more people are about to die in some lethal contraption. Who could have seen that coming?
As much as the Saw films rely on their central conceit to attract the audience (assuming the whole trap angle was what brought in audiences, and that seems to be the case), then it's going to keep going back to the same well again and again. The more it goes back to that well, the more it has to up the stakes to keep people coming in. The more it ups the stakes, the less important other aspects of the film become. The original movie has been photocopied over and over and over and over and over and over, and all of the weird shades of obsession and duplicity and secret lives from the first movie have been reduced to blobs of traps and bodies to occupy them. There's no actual story any more, just a pretext and series of set pieces.
So that's the first problem with sequels: After the first movie, there's no real mystery. Successive sequels take the parts of the first movie and replicate them at the expense of anything that wasn't one of those parts. Mystery, so important to horror, is replaced with expectation, and narrative is sacrificed for spectacle.
The second problem stems from the first, to some extent: You can't completely abandon narrative for a string of murder scenes. Oh, sure, it'd probably be more efficient, but I suspect that lays the real value of those movies a little too bare for comfort. So what we're left with is the need for a narrative (or plot) that provides a reason to revisit a particular setting. Jigsaw needs more victims for his games. Teenagers need to return to Crystal Lake. Someone else needs to have a near-death experience in order for Death to catch up with them. Someone else needs to pick up the Lament Configuration. The spirit of Michael Myers needs to inhabit another body. There needs to be a reason, no matter how spurious.
The pretext can be handled with varying amounts of finesse. At one end, you have the Hellraiser movies - since the engine of all of the horrible stuff in those movies is a puzzle box, it gets handled more like an anthology than a continuous narrative, and although there is some throughput and some attempt at a mythology (to the movies' detriment), it doesn't become problematic. At the other end, you've got the Saw movies - from an original movie which itself had a pretty elaborate storyline, attempts to continue with entirely new setpieces and groups of victims have made what was already a complicated narrative downright unwieldy. The Jigsaw killer is already dying in the first movie. He doesn't actually expire until the third movie. There are four movies after that. What follows is a kaleidoscope of secret apprentices, double-secret apprentices, double-crosses, triple-crosses, and somehow, each and every character in every one of the seven movies is somehow connected to all of the others. In the Saw films, there are no strangers or bystanders. Everyone has somehow crossed paths with Jigsaw or someone Jigsaw knew, for good or ill. It is a self-contained universe, with the Jigsaw Killer as the body around which all things orbit. Were the films concluded with the reveal that this was all the narcissistic fever dream of some mid-level bureaucrat who likes to tinker with gadgets in his garage, it'd be good. But not so much.
the Wikipedia entry…
"As William progresses through four tests, he saves as many people as he can and learns the error of his choice to reject so many policies, which inherently "kill" the rejected. His last test is revealed to be a test of forgiveness by the family of Harold Abbott who William rejected a policy to in the past, who ultimately choose to kill William using Hydrofluoric acid. Meanwhile, Agent Erickson and the previously thought to be dead agent Perez search for Agent Strahm with the assistance of Hoffman. Upon finding irregularities in previous murder scenes, Perez and Erickson discover Hoffman's identity, but are killed by him before they have a chance to report him but Perez tells Hoffman that everyone knows about him. Hoffman then plants Strahm's finger prints on evidence in the room where he killed Erickson and Perez. Hoffman travels back to the site of William's tests in which Jill attacks him to obey John's final request. She leaves Hoffman in a new Reverse-Bear Trap left behind by John where he is able to manipulate the trap and escape wounded. Hoffman is left in the area, screaming, with his face mangled by Jill's trap."
It's like a soap opera. With knives.
Ironically enough, even as the individual movies suffer a paucity of story (lots of people in traps, there's a twist somewhere, roll credits), the connections between movies make trying to follow even the meager story there is almost impossible. Not every franchise has this particular problem to the degree that the Saw films do, but to one extent or another, each revisit to a particular well entails stretching the confines of the original story to accommodate more and more iterations. Again, we lose the sense of mystery that makes any horror film powerful, simply because additional movies stretch plausibility further, both in each specific story (yes, lightning did strike Jason Voorhees' grave and that's why he came back. Also, his heart is a demon), and as metacommentary. The more movies there are, the less finality the events of any one movie have. Nobody is actually in mortal danger, because either they are necessary for the inevitable sequel, or because they are just day players in yet another installment of a franchise. Their peril has no meaning, and so no power to move us. Copies of copies of copies.
I'm not saying stories should never be revisited or that sequels are never warranted, but it seems like more and more often horror films are being made with the tacit acknowledgement that there will most likely be a sequel if it's successful, and some are even openly referred to as "the beginning of a franchise." That isn't art. It's product. And I firmly believe that horror films are, at their best, capable of being art. And I want to see horror movies at their best.