I approached this 'special' episode with trepidation because I hadn't been too keen on the last one, and felt that the sense of character continuity and chemistry the Doctor had built up in the last full series of Doctor Who had been lost. However the bond between the Doctor and his one-off companion Lady Christina (played so saucily by Michelle Ryan) is very swiftly established and keeps going throughout the story.
The story rattles along at a fair pace, the Doctor making us laugh while staying serious, and entertaining us throughout. The plot is clearly a rip-off of an old James Stewart film, Flight Of The Phoenix, and principal writer Russell T. Davies admitted this, however at least it was a good idea he copied, and the story fits the new, slightly lonely Doctor well. Tennant's portrayal is up to his usual standards, and there is a small ensemble of supporting actors to move the drama a long.
The alien races encountered here are not very original (insect-people and flying manta rays), as is often the case they are just adapted from animals we already know (like so many in the last four years). However this doesn't detract from the drama of the story; the bad aliens are very well-realised by computer graphic effects and the sheer speed at which they move makes them frightening. The good aliens are also brought to screen believably, and made me feel like we were dealing with real alien people, rather than just a 'monster'.
Supporting all this back on earth are UNIT, a reassuring presence in the form of Captain Magambo, and her dead-pan practical nature are a welcome foik for Lee Evans's manic scientist Malcolm.
Framing all of this is the brilliant cinematography. The sight of the Doctor and Christina strolling out on miles and miles of untrodden sand will long live in my memory, as much as the images of the London bus stranded in the desert.
I recommend this to anyone who enjoys Doctor Who, it's a good one!