Disclaimer: I have never and will never like Captain Jack. I never much liked the other cast regulars either and I had major issues with the entire Torchwood premise. I felt like what potential it had was largely jetisonned in favour of being the 'Jack is a Big Damn Hero' show. And with Barrowman's attrocious acting that just wasn't something was up for.
That said, Jack was at his most interesting in this arc. Which is to say: he was interesting! :D They finally used him as an anti-hero--whoooo hoooo! IMVHO, that's how he should have been used all along. His flexible morals, his shallowness, his egotism... these are not heroic qualities. What I loved more than anything (and I've got a lot more on the 'love' list) was that this showed that what makes Jack 'special', more than anything, is his ability to do unthinkably awful things for the greater good. Did he save the world? Yes. Did he make himself a horrible pariah of a being in the process? Yes. Furthermore, while has the courage to take the distasteful actions, he does not have the courage to live with the consequences--he runs from them. The consequences of his actions in 1965 catch up with him here, which implies that he can't run forever from his darker actions. I loved that his action in 1965, taken without much hesitation, was pointless and even detrimental--the aliens just came back with more threats. His actions in the current timeline, however, do appear to be successful--but he had to pay a terrible price for that, and I am really REALLY impressed that the show went there. This is heroism of a very dark kind, and I am entralled. Jack at his darkest is a lot more sympathetic to me than Jack the flirty, narcissistic 'hero'.
On a wider scale I was really impressed with the plotting of this five-parter. It was gripping, suspenseful and tightly controlled. Every minor detail built into the overall story, with B-plots reflecting the larger A-plot themes. While I wasn't very interested in Gwen's pregnancy on Ianto's family and coupledom angst, I found them watchable as part of the wider plot, which made sure to show us human consequences of the central crisis. Notably, where many shows allow most of the victims of a plot crisis to be faceless voiceless characters, here the majority of the victims (with the exception of the kids in 65) were 'known' to the audience. Ianto, of course, being the most well-known, but Jack's grandson, Clem and Frobisher's family were well established within this season.
The writing was courageous too in allowing so many of the characters to be unlikeable. Frobisher was absolutely fascinating and I found his journey moving and gripping. As a study of bureaucracy and the dangers of groupthink, the government sessions (while necessarily caricatured for brevity of message), were chilling. If the prime minster wasn't chilling enough, the woman that moved in to take over from him at the end was the very one who advocated the 'lowest percentile' use of the school tables. (And how dark was that?!) Frobisher, as an imperfect everyman caught in the system, became a tragic and chilling figure, and I loved the way he paralleled Jack.
In terms of suspense I've rarely seen a more gripping arc--by part 4 I was thoroughly captivated and impressed, but I was still sure that the end would be, in come way, reductive. Jack would, I was sure, get his 'big hero' moment (yawn), and there would be some shortcuts in the resolution of the alien plot. I never expected how fully they would avoid the reductive 'clean slate' ending. Yes, they did magically find a way to kill the aliens, but the price for that was so dark and so personally emotionally challenging for Jack that the suspense was completely maintained. And how wonderful that the three 'heroic' figures in that final scene were so unlikeable--Ms Johnson was perfect at getting things done, the mission-objective-obsessed lackey; the tech guy whose name I forget was a horrible 'low-key' bottom feeder (his 'I just stood back' line was so chilling!) and then there was Jack The Unkillable.
Speaking of which, this is another way in which Season 3 made better use of Jack than ever before: by exploring the horror inherent in the idea of a man who can never die. The horror exists on multiple levels. It exists in personal physical horror (Jack reconstituting himself in screaming agony) but it also exists for those around him--because as Alice says 'a man who cannot die has nothing to fear'. Perhaps the only thing he does fear is what he runs from at the end--the weight of his conscience, grief, and other emotional consequences. But he can just run. And does. Alice was wise to stay away from him, though I liked that her emotional connection to her father was also evident. It is absolutely tragic that her one moment of faith in him--when she convinces Ms Johnson to free him--was her undoing. As an innocent, her son was the perfect victim--Jack never got to know him properly, but his death will eternally fuck up his relationship with his own daughter. And I love that she had no words for him at the end. There are no words that will ever repair that rift.
I really enjoyed Lois, though her infiltration of the government was pretty implausible. It's the sort of thing I handwave on Who though, so I ran with it. She was a really likeable figure, and I loved that they used her PA skills of awesome! I also liked that Frobisher's loyal secretary got to play her own 'heroic' part.
Clem was also a wonderful character. I loved his reaction to Jack, a signal of what was to come. The idea of Jack as a figure of childhood nightmares really works for me. Clem's connection to the aliens provided a great deal of suspense, and his 'disconnection' from them was horrible.
Ianto's death would have been more affecting had I been attached to him. As it was, Barrowman's acting was really stretched to the point where I LOL'd involuntarily during the death scene. But I did find Jack awaking among the body bags, with Ianto unable to escape his quite poignant, conceptually at least. I also really liked Ianto's very ordinary sister and her revelation that Ianto was a bit of a trickster himself (which I remember from season 1 as well). Ianto seems to have been a bit of a 'Jack light', and the inherent narcissism involved in their ship kind of turns me off, but is interesting as an idea.
I never liked Gwen but here, her inherent characteristics (star-struck about Jack, naive) were also shown to be limiting. Her disbelief that Jack would really run away at the end helped make that scene a lot more effective. To me, it was obvious that Jack would run from the moment he made the decision, and probably from before that, from Ianto's death. I don't think he wants to live 1000 years remembering Ianto--that would be agony--and I think Ianto was right when he suggested that there was a lot more darkness beneath the surface of Jack. I like that we'll never really know.
The aliens themselves? *shivers* Great sci fi work there with having us not see the aliens properly--they were way more scary that way. And when they said 'the hit', I was awed at the horror. Kids as drugs. Wow. Their slowed-down speech could be read as drugged-out, though I had previously thought that it was an attribute of their species. I had so easily fallen into the trap of assuming, trained by Who, that the aliens needed the kids to live. To discover instead that they were a drug made the government's decision to sacrifice 10 per cent far more disturbing. It seemed really clear that the druggie aliens would just come back for more later.
There were limitations to this arc. For me, most grating was the fact that everyone just gave in so quickly and seemed to take it on faith that the aliens could destroy Earth at will. But that paid off when Jack strolled, all so arrogantly in, and achieved absolutely fuck all by being a hardass in negotiation. It was kind of two extremes of fail--underestimate massively or overestimate massively. I'm kind of glad UNIT was shown as slightly more effective--they at least worked out the aliens' objective. There were plenty of other nitpicks (the aliens took their atmosphere with 'em?) but these were small scale in the bigger scheme of things.
The main thing for me is that it's so rare to see an arc so well plotted that does not COP OUT massively at the end. It's also rare to see a television show willing to let its central characters seem limited or even unlikeable. I applaud Russell for this work--it is very encouraging to see such television out there!