It's pretty interesting, you can find the videos on Google Video, each is about 1 hr long but you dont really need to watch them, as much as just listen to them when your doing something.

Part 1 - Baby It's Cold Outside
http://video.google.com/videoplay?docid=461187809452836609
Part 2 - The Phantom Victory:
http://video.google.com/videoplay?docid=2940187978111229279
Part 3 - The Shadows in the Cave:
http://video.google.com/videoplay?docid=-2324388902129396093

I don't exactly think the BBC is a bunch of radical liberals or Michael Moore, so I think its fair to say you can take the documentary with atleast 2 grains of salt.