Youth is a predominant factor. We are seeing a young King Arthur, and thereby a young-ish - as I'm into my 40s - Merlin. It was about how to tackle it, from that point view.

There are a couple of films that I've done, where I've had to get on a horse and wear a pair of tights, so that helped. But, nothing could have prepared me for the fun of wielding magic like Merlin does, especially in the perverted mind of Chris Chibnall.

I wanted to say, "Hey, Pope Francis," but I cried like a baby. I was reduced to a very humble set of feelings, because it was not about what was said: There's a presence. That was a blessing for myself and my family and everyone there to be a part of that.

A large part of how an actor works and their process is the stimulation of what's around you, and none more so than in a period piece. This is a modern piece, as much as it is set in a different time, age and myth. If it wasn't relevant, it wouldn't have been made and we wouldn't be putting our energy into it. It's relevant for us today because, in some ways, it throws up a mirror to all of us. As an actor, you get stimulus and you're effected by that, whether it's costumes or funny beards or castles.

I fall in love with contradictions without understanding. I can't really portray them unless I do. So in a roundabout way I have to fall in love, it's my duty. If love is about understanding and understanding is compassion and compassion is love, I have to have compassion towards the world.

I'm a huge admirer of Pope Francis and everything he stands for. I think he's an incredibly connected spiritual and authentic being.

He [Merlin] is slightly from another world and place, so it [challenge in bringing the role to life] is about having fun and presenting it in a new way. He's more of a politician, and slightly Machiavellian, but there's also a lovely relationship going on between Merlin and Arthur. There's so much to be had, really.