Because I was always a fat child, I got fatter and fatter, and I ended up 18 stone and with a 40-inch waist.

My mum and dad have always enjoyed life, and it's something that's been instilled in me. I wake up in a good mood most mornings.

I love doing comedy, I really do. It was perhaps my first love. And I think, as an actor, you're young and you do school plays and the reason you go 'I might do more of this' is because you make people laugh in a school play. You don't go and do Hamlet when you're nine and go: "I feel people were really moved out there!" You do a silly voice and everyone laughs and you go: "Ooh, that feels quite nice. I might make a life out of this!"

Doing Prometheus was what you imagine being an actor is like when you're five. In a spacesuit, on another planet, getting killed by an alien. It was a real treat, it felt like being a part of movie history.

I've done loads of things people have never seen, dramas on BBC4 and plays upstairs at the Royal Court and the Bush, and because I didn't go to drama school, they gave me an education.

I'm sure that my father becoming seriously ill when I was 14 had a lot to do with my going from chubby to fat.

There's nothing so unattractive as vanity... particularly male vanity.