When you're surrounded by friends and exes, there's a whole lot of stuff that starts crawling out. But however serious and traumatic those experiences may be to the participant, to the onlooker they're hilarious.

I wouldn't mind removing all the mistakes I have made. That would be exhausting and take forever. Honestly, it's one of the spells of my life that has been the most perfect. Not because I did the job perfectly, because of course I did it very imperfectly, but because I enjoyed it so much. What would I change? I complain a lot. I whinge, I more or less communicate in levels of complaint so I wish sometimes I didn't just spend all my time saying, 'I'm working so hard, what do I get in return for this?'.

I'd forgotten not all victories are about saving the universe.

I can say with pride verging on smugness that I've got two very successful shows that assume their audience is very smart.

My problem is that the audience is more fiction-literate than ever. In Shakespeare's day, you probably expected to see a play once or twice in your life; today you experience four or five different kinds of fiction every day. So staying ahead of the audience is impossible.

Well we've moved through the funfair a bit – we've done the rollercoaster, now we're on the ghost train.

The trouble with a series as it gets older is it can feel like a tradition, and tradition is the enemy of suspense, and it's the enemy of comedy. It's the enemy of everything, really. So you have to shake it up.