"The Poison Sky"

Yawn. This finale isn't bad per se but it's not very interesting. I think the problem with all of these two parters is that realistically they don't have enough content to drag them out for two episodes so they get padded with all this needless bulk. There are long shots of smoke filling various Earth locations and extended scenes of Sylvia and Wilf sitting around in their house and very time-consuming bits of Donna just hanging around in the TARDIS not doing anything, UNIT people sitting around not doing anything, and even the Sontarans essentially just standing around not doing anything. Clone Martha seems to exist for no purpose other than to block Earth's nuclear missiles repeatedly and after taking ages to discover that the Sontarans are trying to convert Earth into a clone world the Doctor grabs some magical device from Rattigan's house and 'ignites' the atmosphere to restore everything to normal within the space of about a minute. Then there's a heartfelt farewell as the Doctor thinks he has to sacrifice himself to defeat the Sontarans but in a way that is somehow meant to involve him achieving his potential Rattigan swaps himself with the Doctor and kills himself to take out the Sontarans instead.

I have a whole load of questions. If the Doctor has reconfigured the atmospheric ingiter to work on 'Sontaran air', how come the Sontarans seem to breathe normally on Earth? Also, if on Earth the igniter just puts a nice carpet of fire along a high altitude which burns up all the noxious gases but doesn't seem to harm the Valiant or the top of the Chrysler building or anything in any significant way, how come it causes the Sontaran Mothership to spectacularly explode so violently that not even debris remains? If the fire just breezes along high up, how does it wipe out the gases which seem to be sitting low to the ground, and how come it doesn't also consume Earth's natural atmosphere? I suppose once you've come up with some kind of impossible thirty-second planetary atmospheric conversion system there's no rational way of explaining it and it can work however you choose but that's not very satisfying.

The Tenth Doctor is far too shouty and indignant, UNIT becomes absurdly obstinate and stupid apart from their deployment of the Valiant, and Rattigan ceases to be interesting and becomes a sort of pseudo-Objectivist nutcase who lies on the floor of his teleporter crying. I really hate how they overuse the word 'clever' as well, as if it's the only term for intelligence. It sounds like school children having a conversation about the smartest kid in the class and it ceases to have any meaning. The presence of Martha is virtually pointless and while the Sontaran ship interior looks pretty cool and is kind of reminiscent of a classic series spaceship set, the section of Donna wandering around and the whole concept of teleporters being deadlocked open and closed is kind of ridiculous; as usual we just have a lot of the Doctor waving his sonic screwdriver magic wand to cause plot points to happen without any real explanation.

As with the first part, I'm not sure what else there is to say. I suppose it's an okay reintroduction for the Sontarans and the battle sequences are pretty nice but the plot is absurdly complicated. Why couldn't the Sontarans just attack, kill everyone and gas the place? Or even just gas the place and let that kill everyone? Why did it need the cars? It reeks of RTD going "Oh I know what'd be funny, car exhausts that actually kill people. You know what? Let's throw the Sontarans in, haven't seen them yet. Helen, you can make it work, right?" and that's that. A lot of the characters feel very arbitrary, especially Martha who spends too long as a clone to even justify her presence in the story beyond fan service, and as usual it has nothing to say. It's watchable but there's just nothing more to it. Sometimes I feel like in this era beyond the finales and building up to the finales they didn't really care.