Charlie Casanova is not a film you watch and forget.

Irish writer/director Terry McMahon’s grungy hard-hitting character portrait follows a self-obsessed sociopath named Charlie (Emmett J. Scanlan) who runs over a woman with his car and decides, Two Face style, to draw a card to determine whether he calls the police. His business is struggling, his marriage is struggling, his relationship with his father is struggling but Charlie, bitter and masochistic, doesn’t make life easier for himself.

Described by The Guardian‘s Peter Bradshaw as “unbearably and unintentionally obnoxious,” the film — bold, audacious and coloured with a kind of scuzzy, tortured pessimism — has been selected as the opening night feature of this year’s Melbourne Underground Film Festival, which kicks off on Friday.

“The ‘overground’ critics despised it,” McMahon tells me. “Their personal attacks were borderline hysterical and the way they banded together to attack the film and its maker was unprecedented.”

Charlie Casanova has however been embraced by underground film enthusiasts, and not just in Melbourne. Its bona fides include taking the top gong at the Dublin Underground Film Festival last year.

The colourful and self-effacing McMahon doesn’t mince words when quizzed about the film’s many talking points — or his place in the film industry.

“I consider myself a hack-whore who doesn’t want to forget how to kiss,” he says. “Having written bad television soap-opera for years, I can’t claim any anti-mainstream integrity. Nor do I want to.”

There’s a fly by the seat of your pants kind of gonzoism about Charlie Casanova, a sort of grungy sadism that weeps from the screen. What was the atmosphere like on set? Were there any off-screen exploits as gnarly as the things we see in the film?

Gonzoism is the perfect word. The atmosphere was insane but in an exciting way and illusion and reality becoming blurred became the fuel behind the film. The actors and crew didn’t quite know if the writer/director was a madman or an asshole or both but they dived in deep and trusted the bizarre world of the script. Emmett Scanlan, who plays Charlie spent some private time messing with the cards and did some shit he should have been arrested for but it’s a testament to his brave immersion as an actor that he went that far and an indication of his ingenuity that he never got caught.

Charlie is a loud, violent and extravagant character with strange sexual peccadilloes and a smorgasbord of faults and flaws, surrounded by an overall air of menace. Do you know anybody like this? Have you met anybody Charlie-esque?

Multiple modern Irish politicians and their protective media folks posses all those qualities and worse. More than Charlie-esqe, these sickening posers are unashamedly Cunty-esque.

Even when Charlie does stand-up comedy, there’s a pervading air of sickness about it, and him — a kind of intoxicating strangeness, as if he’s performing to himself. Do you like this character? Do you hate him? What interests you about him?

I abhor Charlie, which is the very reason I wanted to explore such delusional scum – to take all my prejudices against the controlling class and force feed their opposite into the mouth of a man with the self-loathing of a Charlie Casanova.

Charlie Casanova has been selected as the opening night film at MUFF. Do you consider Charlie Casanova a quintessentially ‘underground film?’ If so, what do you define as ‘underground’ cinema and does Ireland have a strong underground film movement?

I’m not sure what kind of film it is but I do know the ‘overground’ critics despised it when the film was picked up by the legendary Studio Canal for cinema distribution. Their personal attacks were borderline hysterical and the way they banded together to attack the film and its maker was unprecedented. However, Dublin Underground Film Festival awarded Charlie Casanova Best Film last year so maybe that answers it more than I realise. Dave Byrne and Denise Pattison run Underground in Dublin and they do astounding work facilitating films and filmmakers.

Characters in Charlie Casanova slam the working class throughout the film but the film itself – particularly in terms of how it was shot an edited – has a strong working class vibe. Where do you come from? What part of society? And what is the relevance of the characters’ expressions about working class society?

The last few modern Irish governments have destroyed Ireland. Doing deals with the most despicable devils they have rendered Irish democracy little more than a eunuch in a European whorehouse. Bailing out un-guaranteed bondholders they are systematically attacking the poor, the vulnerable and the weak with policies designed to use poverty as a weapon of extortion and control. Charlie’s incremental steps towards a murderous expression of prejudice is an obvious metaphor for those policies. I am working class.

Charlie Casanova was made on a small budget. There is a police interrogation scene that feels realistic because the cameras linger so close to the characters and you don’t get a geographical sense of where the room is. Was this decision to frame the film intimately around the actors a product of a budget work-around?

I don’t know how it is for you but in my nightmares I never have any idea where I am. Geography and location are roobed from me to enhance the head-fuck. I wanted Charlie to be the same thing, where the only real landscape to watch is the human face and, even then, you’re not sure if that face is lying to you or not. Charlie is a pseudo philosopher, a pseudo intellectual, a pseudo lover. Charlie is almost a pseudo human being. The only emotion he feels is real is fear and I wanted to get in close to see that. The rest is bullshit facade and he uses torrential language to divert you from looking at him in too much detail, just in case you expose his cowardice and lies. Charlie is most Irish politicians.

As a character Charlie is very hard to like. Even his own dad says to him: “half the time I haven’t got a clue what you’re talking about, son.” And then you cut to Charlie staring at himself in the mirror, looking terrorised. Did you intentionally create this character to offend people? To take them outside their comfort zones? If so, why?

We wanted to subvert the standard notion of empathy, understanding and comprehension. There is no third act catharsis. There is no moment of humanity. There is no redemption. Charlie feeds on innate decency. Charlie feeds on people’s desire to believe in better. Charlie feeds on ideology. Charlie may appear harmless in his three piece suit but he’s planning to rip you off; you and your head.

Do you consider yourself an “indie” or “alternative” filmmaker? If so, why, and what is it about mainstream filmmaking that you despise, if anything?

I consider myself a hack-whore who doesn’t want to forget how to kiss. Having written bad television soap-opera for years, I can’t claim any anti-mainstream integrity, nor do I want to. Hollywood makes some horseshit, yes, but there are also occasional masterpieces sneaking out of there too, for example, Tree Of Life stunned me last year and I can’t wait to see The Master.

Charlie Casanova is playing at the Melbourne Underground Film Festival.