“I thought after Children of Earth, how do you top that? If you can’t top it, don’t come back. What we try to do every year is tell a different story. Some might like the more alien stuff, some might like the domestic stuff, but you can’t ever say it will be boring or samey. As long as there’s Russell T Davies, there is life in Torchwood.

“I can’t quite put it into words. There isn’t a second that goes by when I am doing my job where I don’t grab hold of every inch of it and try to absorb it and enjoy it more. Because it is massive. It’s huge. When I’m not on the job I am talking about the job – and all I talk about is Gwen Cooper, and I hope I never, ever take it for granted.”