Fountain of youth' is actually kind of ambiguous - does it mean a way to make everyone healthy and let them live indefinitely? Or are we talking about something that would reset you physically to the way you were in your youth, which for various reasons not all of us would be enthused about?

I've been surprised at the number of people who were really angry that I tried to convey gender neutrality by using a gendered pronoun.

I suspect that we get used to particular sorts of stories being presented in particular sorts of ways, and we're so used to interpreting them and understanding what it is they're doing that we think of those forms and styles as faithful, complete depictions of reality.

Science fiction in particular is often assumed to be about the future, or about some abstract technological or philosophical idea, or just about 'adventure,' but writers can't build worlds out of nothing. We use bits and pieces of the real world to assemble our fictional ones.

The majority of my family is in Jersey.

I do recognise I have a responsibility to the audience. They feel fairly confident that if I'm in something, they can sit down with their family and be entertained by it. I don't desperately want to change that.

What I continue to learn as a parent is to be mindful of the fact that I am responsible for being the parent that my children need me to be and not necessarily the parent I want to be.

We started watching 'Doctor Who' as a family because our first daughter was a cranky baby, and she would get up during the night - and it was her dad's job to stay up because I worked at night.