We don't see Jigsaw (Bell) or Amanda (Smith) for twenty minutes into the film - in fact, the lead character we follow, Lynn (Soomekh) is not seen for 17 mins in - after we see the opening of Matthews foot-smashing sequence, Troy's chains-in-the-body trap and then, we follow Kerry (Meyer) mourning the loss of Matthews and seeing him in mirrors in her house. I assume technically speaking, we initially think we are following Kerry's character and then find out - when she is literally ripped apart - that we are not following her at all. Enter Lynn.
So Jigsaw - other than in flashbacks - is only in a bed. Yet, his prescence is powerful. He completely controls everyone around him when - at any point - they could easily think, fu** it. "I've had enough... if I walk away now, only you take the fall". No one does of course because Jigsaw is scary. Even bed-ridden and incapable of moving, he remains as someone you don't want to annoy or anger.
As always, we are filled in on back story and how much Amanda has been a part of Jigsaw's plan. She assisted him when setting up the room in Saw which, as a fan, is incredible to watch. Jigsaw putting himself into the position that we only knew was important at the end of the film. Jigsaw, effectively, setting up the 'twist' at the end of the incredible first part of the series. Problem is, all the new traps have a problem which is explored in this film and, ultimately, is problematic. Amanda starts killing people - and not giving them a chance to escape. We know Troy could never have survived, we know Kerry had no chance of survival - and so the moral question as to 'live or die' is not raised. We merely see impressive, artistic traps - that have no feasible escape route. This may be a neccessary aspect to the story ... but the whole moral conundrum that Jigsaw sets up is not adhered to. We have to wait until part IV until the traps become more ... [im]morally accurate to Jigsaw's vision. But then this is a part of the themes of this film - the training of an apprentice and, what if, they were trained wrong or the potential 'legacy' of Jigsaw was going to be ruined. Amanda is a weak character by nature - she has problems with drugs and self-harm - and even after being accepted by Jigsaw, we see her retreat back to these problems. So, we see how this is dealt with and - more importantly - how Jigsaw was aware of these problems. And acted.
The filmmakers go further into doing something which, personally, I didn't think was entirely grim but - apparently - most people find incredibly difficult to watch. At one point, Jigsaw (Bell) on a bed, is put into surgery and we see some brain surgery as Doc' Lynn (Soomekh) takes out a brain tumour. On the one side, seeing the cutting-away of the skull and the gooey mess taken out and what-not is quite disgusting. On the other side of things, I can imagine a doctor probably sees it as work. Might just bore you if you were a doctor. A similar thing happens in Saw IV whereby you see, on one hand, a disgusting gory sequence but also a normal procedure on the other hand.
One thing to praise the filmmakers for is the multicultural nature of the cast. We have this new docotr Lynn played by an Indian actress, while Rigg - star of Saw IV is African-American. There are many more examples of multi-cultural roles and, upon reflection, it works incredibly well to make it more realistic. In this film, the revenge-obsessed Neil (Macfadyen) is blaming everyone else for the death of his child in a road accident and when he comes face to face with the driver of the car, this driver is African-American. We see in flashback how upset and destroyed this man was following the accident. It is Neil who is in the wrong - purposefully going out of his way to stay angry and mentally acting out fanstasies of murder, while the 'actual' murderer is no murderer at all - he is a man who made a mistake. The first film had Danny Glover and Ken Leung amongst it's cast - African-American and Asian actors respectively (though both born in the US), so clearly this is an important part of the casting process of these movies.
Influences, according to Whannel, are - amongst others - Dario Argento. A little typing of the words 'maggot soup' and 'argento' on Google bring up a blog (not too dissimilar from this one) that notes Argento's Phenomena as a Freudian soup. The picture also shows Jennifer Connolly in a disgusting swamp. Anyway, getting off the point a little. Leigh Whannell explained how a sequence in Saw III whereby a Judge is drowned in pig-guts was taken from an Argento film whereby a character swam in maggot soup (possibly Phenomena... should watch it). So it is interesting to think that Whannell has aspirations of credibililty on a par with Dario Argento ... co-writer of Sergio Leone's Once Upon a Time in the West. It's one thing to want your movies to be up there with Jonathan Demme and David Fincher. Another when we are looking at Sergio Leone and David Lynch.