So, as opposed to getting people in to read the script and read scenes with me, what I wanted to do was sit down and chat to these people and just say, "Okay. Do you share my sense of humor? Do you understand what this film is getting at? Do you know the tone that we're trying to get to?" And it was interesting.

It's incredibly easy as a director to be egotistical. Of course, it is because you have 200 people on set every day listening to your every word and whatever you say goes, and that can be slightly corrupting. And actually, to be a good director, you have to take ego out of it, because hopefully what you've done is surrounded yourself with brilliant people. Let them be brilliant and you just shepherd that and marshal that and hopefully guide it however you can, but definitely not to the extent that you're overbearing.

It's tough to make funny films. And the truth is, with this process, especially if you write your own movie, then you're giving three years of your life to it. And so, I just have to be sure that when I embark on it that I'm happy to think that in three years' time I'm going to be sitting in a room on the tenth floor of an odd office building at Ginsberg Libby talking about it. So I'm keen not to jump into it too quickly and just make sure it's something that I really want.

In terms of magnifying it and making it plausible, I'm a great believer in truth in comedy.

I like to foster an atmosphere on set of collaboration and openness and risk taking. The beauty is when you have such brilliantly talented people as I did in my cast, you definitely don't want to fetter them in any sense. You want them to be able to go out there and do their thing and feel confident in doing their thing, because ultimately I'm the person who gets the credit which is great.

So, as opposed to getting people in to read the script and read scenes with me, what I wanted to do was sit down and chat to these people and just say, "Okay. Do you share my sense of humor? Do you understand what this film is getting at? Do you know the tone that we're trying to get to?" And it was interesting.

You sit down in the morning on your own to write something. You get to the end of the day and it's not like you've cracked it and it's finished and it's done, because it can always be improved. It can always be changed. There is no right answer, so you can drive yourself crazy with just the expanse of infinite possibilities when it comes to writing.