Ah, now I get it! Thanks so much for the very detailed explanation, and the links. And boy did I grin when I saw that Wood is played by none other than David Tennant! I knew that he had done some work for BF before becoming Ten, but had never actually got around to looking it up. I do have few BF audios; mainly Eight (who, annoyingly, my OH insists doesn't exist, so for him Matt Smith is Ten, not Eleven... grrr!) but I do have one with Seven (I think its called 'Master'...!). I will make a point of looking this one out, definitely.

*Hurries off to read*