Patrick's Day is a searingly powerful new film about a 26-year-old schizophrenic Irishman whose mother becomes enraged when she discovers he’s having an affair.

Starring Irish film-star in the making Moe Dunford, 28, the film follows Patrick as he squares off against his increasingly controlling mother Maura (played by Kerry Fox) who wants to decide who he can see and not see, whom he can love and not love.

It's all for his own good, of course. Maura only wants to protect him. It couldn't be anything more than that, could it?

Director Terry McMahon has a gimlet eye for low key but lethal Irish authoritarianism, the kind which marked most of the 20th century and makes Patrick's Day one of the most disturbing and engrossing new Irish films seen in years. Dunford won last year’s Best Actor Award from the Irish Film and Television Network for his work in the film.

“When you become a ghost in your own life through homelessness your skin becomes transparent and you feel things you wish you hadn't,” McMahon tells the Irish Voice.

“You become horribly aware of the national psyche as its cowardice tries to drive you to diminish yourself then die by your own hand. You romanticize your death as if it has poetry then realize pretty quickly that nobody gives a damn. So you fight to live and get toe-to-toe with the self-loathing and malignant shame that we all seem to have inherited.”

If that sounds like McMahon has some pointedly provocative things to say about Ireland, well, he's only getting started.

In Patrick's Day a mother's love very quickly becomes a metaphor for a reflexively conservative and censorious Irish society reacting to the destabilizing threat of the young.

“Being Irish is an ongoing battle between romanticized poetry and horrific reality,” he says. “Some of us have killed for it. Most of us ignore both.”

In the film Dunford, at the time of casting a relative newcomer, gives a for the ages performance. (Dunford plays Aethelwulf in the History Channel hit Vikings.) What made McMahon choose him?

“Moe was an unknown entity and therefore an understandably risky pick for some of the financiers but there was a raw power in him that I have rarely seen in 20 years of teaching acting,” McMahon said.

“Turned out he's a magnificent young man on and off the camera, a one in a generation, talent and now he's about to do three movies back-to-back. I love the kid and I love that the producer, Tim Palmer, the casting director Rebecca Roper and the financiers had the balls to back my potentially perilous penchant for an unknown.”

Is making an Irish outsider the focus of Patrick's Day and then calling the film by the name of our national saint and international celebration of Irishness is a pushback against the silence that falls around the freaks and misfits at home?

“The Land of Saints and Scholars is now the Land of Charlatans and Scumbags,” McMahon says.

“Like pimps destroying everything that is noble about the love of our country, successive governments have sold much more than our soul to magpies and vultures. We are in such a state of revisionist shock that we resemble Patrick's electro convulsive therapy in our determination to deny our reality.

“Worse than Patrick's dehumanization, there are innumerable people dying due to the cancerous policies of austerity imposed by men and women who should be ashamed to call themselves Irish. Yet, just like the psychologically broken Patrick, we have invited our own abusers back into our bedrooms in the recent elections.

“On the centenary of 1916 we have done irreparable psychic damage to the most vulnerable of our society as the abusers swagger away with impunity. I despair at the state of our nation but at least the left is finally having its voice heard and maybe, just maybe, we might collectively use democracy to kick the scum out of our bedrooms and protect our children's future. Maybe.”

Because he can talk like this, and write and direct like this, McMahon's career will be a once in a generation Irish story.

Patrick's Day is now available on iTunes. It is available to preorder now on Amazon VOD and will be released on DVD on April 5.