The episode was a definite fast action romp, with the previously leaked chase sequence turning up pretty early on, as Donna, the bride in question takes a taxi in order to try and get back to her wedding, which from the pre-credit sequence, she mysteriously vanished from as she was walking down the aisle.
The question of how she transferred across billions of miles of space from her wedding into the TARDIS was explained as being due to her being saturated in Huon particles, a small amount of which are present in the heart of the TARDIS itself. Presumably the large amounts of power that the Doctor had been using to make his last communication with Rose resulting in the long distance attraction of the particles in Donna bringing her to the TARDIS. The Doctor uses the same effect later in the episode to bring the TARDIS to Donna.
It transpires that Donna has been inadvertently working at a company that was formerly part of Torchwood, but following the destruction of the London Torchwood at the end of Doomsday, the company is now being used as a front for the Racnoss, the last of whom is using the resources of the company to try and revive members of her race who had been hidden millions of years ago in the core of the Earth. The aforementioned Huon particles being used to reactivate them, but needing to be in a large enough concentration, Donna has been used as a human container, with the particles being gradually built up over the previous six months. The wedding is also part of the plan, as the Racnoss human agent had agreed to marry Donna in order to allow him to continue the plan.
Needless to say the Doctor foils the plan and saves the Earth, and the episode finishes with the Doctor asking, and Donna refusing to go with him. Instead, the Doctor uses the TARDIS to produce a snow shower (which probably explains the unseasonal London snow fall in Eastenders I guess) and then departs.
All in all it was a quite entertaining hour for Christmas Day. Donna was definitely different from Rose, and unlike last Christmas where Tennant spent the majority of the episode incapacitated, this time around it was definitely him who was the star of the show. The episode carried on at a breakneck speed, with some spectacular sequences. The TARDIS chase was definitely one of the highlights – and definitely something they couldn’t have done before the advent of CGI. Having said that, the spectacular Racnoss – a giant spider, wasn’t produced in the same way – this was apparently actually built.
The story was dated as present day, dropping it in as a further part of the latest continuity/dating hiccup that I expect will rival the UNIT dating controversy from the seventies for confusion. In much the same way, Rose was dated present day, and then subsequent return visits to Earth were said to be months in the future, particularly Aliens of London which is twelve months later. This pushes the events of both The Christmas Invasion and Doomsday into the future, making both the present day dating of Runaway Bride and the main Torchwood series somewhat problematic.
Anyway, as with last year, the episode was followed by a preview of the upcoming series, with flashes of Martha Jones the new companion, some nice shots of the Globe Theatre from the upcoming Shakespeare episode amongst other things. However, at the end of the trailer we also get confirmation of the return of the Daleks, in a story that is set in Manhattan in the 1930’s. Certainly much to look forward to.