02/08/2012 08:29 BST | Updated 01/10/2012 06:12 BST

Writing Punch - Creating the Darkest of Characters for the Edinburgh Fringe

The central character in Punch is the most heinous, twisted, barbarous person I have ever tried writing. He's impervious to any shred of empathy, tact or compassion and yet I agree with (almost) everything he says.

The central character in Punch is the most heinous, twisted, barbarous person I have ever tried writing. He's impervious to any shred of empathy, tact or compassion and yet I agree with (almost) everything he says. John is a foul-mouthed, vitriolic, aggressive man whose favourite type of comedy is schadenfreud. My challenge was how to also make him likeable enough that people care about what happens to him, or at least give credence to his point of view.

It helps that he gets the best lines. As Mark Rylance (one of our generous sponsors) is demonstrating at the Globe in the current production of Richard III, it can be hard to dislike someone who is adept at making you laugh. The visceral thrill of convulsing with laughter and outrage simultaneously is something only live performance can generate. The bare faced cheek! To say such things and stand so close, thank god it's only a play otherwise we'd have to step in and do something.

I watched and re-watched a lot of stand-up when I was writing the final drafts of Punch. Stewart Lee, Louis CK, Russell Brand and Doug Stanhope were all on my list and very rarely was I offended (although in some instances (such as this) I wondered if Doug Stanhope had gone too far even for me). Why was this? Had I left my moral compass by a magnet? Or was it something they were doing?

In his latest book Stewart Lee explains the complex psychological narrative he takes his audience on during his show - allowing him to take them with him to its scatological conclusion. Russell Brand's foppish demeanour seems to neutralise the shock value of most things he says, that is until they are reprinted out of context by the Daily Mail.

Louis CK and Doug Stanhope present themselves as 'just one of the guys', often laughing at themselves and taking the stage with t-shirt and beers. But these comics clearly aren't just one of the guys nor do we want them to be - they are more articulate and more clear minded than we are otherwise we wouldn't let them get away with it.

The canonisation of Bill Hicks (rightfully so) reflects our need to turn these turns into foul mouthed preachers. But what happens if these saints fall from grace and are proven to be our moral equals, or worse? The discomfort the audience then feels is credited with removing Angus Deayton from Have I Got News For You, and the effect it will have on Jimmy Carr's career is yet to be seen.

In 'Punch' John is accused of far more hideous behaviour than fiddling his taxes, or fiddling with women. Will anyone still like him by the end of the play?

A big part of this is dictated by when and how the audience meets him. It's the same in life. How many parties have you been at when you've found yourself saying the next day, 'Yes, I realise Alan shat himself while he was attempting to have sex with your Nan, but you've got to understand he really is a lovely guy!' It doesn't matter how hard you protest, the person you are talking to will probably never like the guy.

So whilst the play used to start with a litany of the most offensive jokes I could find, now we meet John at a career low: an offensive tweet has cost him all his work, his wife has left him and he's beset by bureaucratic busy-bodies. The stand-up he begins with may not even be intended to be funny; John's gone comedy cold turkey and given up writing jokes completely.

However I knew from the start that it was not good enough to write a play about the idea of offence, if the play was really going to explore it the audience needed to experience offence for themselves. I had to dare myself to find things that were truly unsettling to me; not just explicit or vulgar or in-your-face, but morally suspect. There's not many, as I said at the start I agree with most things John says, but each time they come I hold my breath.

Punch previewed in London at the Canal Café two weeks ago. The reaction of the audience was amazing, lots of laughter and much discussion afterwards. A couple of audience members confessed to a slight state of shock at the end, and I've been getting messages from people in the last few weeks as they've digested the play. In an intimate venue like that, and the Belly Laugh at Underbelly Cowgate is even more so, the actor can feel the revulsion of the audience in a very tangible way.

It is Matthew's job (Floyd Jones, also of Frisky and Mannish) not only to accept it - fighting the actor's natural desire to be liked - but to revel in it. Sitting in the audience I just have to suck it up and hope people approach it in the manner it was intended and that they enjoy what Dickens described when he said of another piece of 'offensive' theatre, namely 'that one secret source of the satisfaction the spectator feels in the circumstances that likenesses of men and women can be so knocked about, without any pain or suffering.' After all, it's only a play.

Punch runs at the Belly Laugh, Underbelly Cowgate from 2-26th August (not 9 or 16). It stars Kirsty Mann and Matthew Floyd Jones and is directed by Jessica Edwards. Tickets are available here.