Then we got Lindsay Crouse, the great Lindsay Crouse. This is the episode where sadly she shines the most and this is her best episode. As often happens, just when things really start cooking, they've got to go. She's one of the bigger names that we've gotten on the show and we know that we had her for a limited time, so there was a practical consideration as well.

It's very much in the vein of Frankenstein's monster and we felt it essential that the first thing the monster do is kill its creator - to hand over the baton as it were and give someone else the villain's mantle for season four.

BBC : Adam himself was interesting in that you had the physical threat of him being part cyborg, part demon. On top of that, though, he was perhaps almost like a motivational speaker for evil - you see him persuading vampires to go into churches, etc.

Doug Petrie: Yes, he was a charismatic leader. We wanted him to be a demagogue and to be very much like one of these terrifying fascist leaders of the late thirties in Europe, take your pick. It's not so much that, "I'm not afraid of Hitler", [but] "I'm afraid of the people who listen to Hitler". That's kind of what Adam was. In himself he's a terrifying creation, but what was really most terrifying is that he was inciting a revolution and demons listen to him.

He had the ability to do what's never been done before, which is assemble an army. So yes, him being a motivational speaker - that's him being able to see into the hearts of demons and say, "Take a look at what your rightful place in the world is." We were touching on something very serious.