I have a great deal of respect for the craft, I don't know how much respect it has for me. But it's a precision process. Doing it on stage would be, I think, terrifying. Doing it on film has its own difficulties, because film is not conducive to spontaneity. You might have a run through and get a few chuckles at eight o'clock in the morning, but you don't keep laughing at the same thing all day long.

So, you don't have laughs as a reference point any more, it becomes a bit of a science after that. And the last thing, you would love to be able to depend on a sense of spontaneity, but hours of waiting and then hours of repetition are not conducive to spontaneity so those are your obstacles. On the other hand it's a lot of fun. Plunging into a bit of physical comedy and abandoning all dignity, no one can really hurt you much after you much after that, once you've done it.

Almost every comedy you see is about people making all wrong choices and making all the errors of judgement possible. Good comedy is when it works on this scale. Because it is psychologically very real.

I thought I was managing my expectations, but on hearing the news I discovered new and unfamiliar vocal tones. Perhaps I should do another musical.

Actors are basically drag queens. People will tell you they act because they want to heal mankind or, you know, explore the nature of the human psyche. Yes, maybe. But basically we just want to put on a frock and dance.

Firth - all dodgy 'tache and frantic eyebrows - has got the sexual allure of a man who runs a swingers' club in Surbiton.

Directors don't get to see other directors at work - they're the only one on the set. I've met directors who've asked me what another filmmaker is like. So, there's probably nobody better placed to make all the comparisons and to pick up stuff than an actor.