Bad Wolf
It always seems to be the way - if the Slitheen turn up, the series really makes up for it in the next story.
"Bad Wolf" was fantastic - finally giving some answers to all those hints in previous episodes. Some nice continuity to THE LONG GAME, and some fantastic satire on Reality TV and gameshows in general. C'mon, admit it - wouldn't Big Brother really benefit from disintegration of evictees?
Of course, some of the tension this episode could've contained has been a little dampened because we know from media coverage that the Doctor regenerates after events in this two-parter, and because the revelation of the dalek fleet was shown in last week's teaser, but even so, the SCALE of that fleet is what fans of the pepperpots have been waiting to see since, ooh, about 1964.
The CGI effects really helped give this episode a sense of scale, and of course, the intimation that the Doctor screwed things up royally really brings us back to that most charming aspect of the Time Lord - he's a flawed hero.
There's the constant teetering on the brink of crossing that sacred Who line, breaking the rule of "the Doctor is never cruel, cowardly or violent", but it brings a human dimension to the character when we see just how much the Daleks push his buttons.
The Controller of the station is a marvellous evolution of the child/battle-computer seen in REMEMBRANCE, and shows just how well this new series links back to the past without alienating the audience. Another example is the telltale heartbeat throb of the Dalek ship.
All-in-all, BAD WOLF is a marvellous opening for a truly epic season finale - lets hope that PARTING OF THE WAYS takes us into the 10th Doctor with a bang, not a whimper.