As a self-deprecating Irish man, actor Pat Kinevane knows how to use wit as a weapon. Thankfully, there is no shortage of it in his latest play, Silent, which tackles the pithy subject of homelessness and its uncomfortable bedfellow, mental illness.
Saying that, Silent is actually more about the exploration of noise, or, to be exact, the relentless clamour of voices that stalk the brain matter of ''Tino'' McGoldrig, a homeless drinker and former man of means who still manages to have a song in his heart and a witty riposte in his tattered pocket.
His penthouse-to-pavement story is told through the prism of the silent-movie era, in particular Rudolph Valentino. Blending flamenco, mime and cabaret, Kinevane sings and struts, diva-like, through scenes from McGoldrig's troubled past that reveal themselves in fragments of painful consciousness throughout the play.
''I've always been fascinated with early cinema,'' Kinevane says over the phone from his home in Dublin (though he is originally from County Cork). ''In the play, the character's grandmother was a huge fan of Valentino and this had an influence on the way he sees the world and the comedy and tragedy in his life.
''In his head, everything is flickering all the time like a black-and-white movie and there's a constant soundtrack playing which he is trying to silence.''
Kinevane is no stranger to mental illness; first as a trainee psychiatric nurse in his youth and later during an encounter with depression in his mid-30s. ''It was a devastating part of my life, it hit me like a truck,'' he says. ''Luckily, I got through it. I had amazing friends, a great doctor and a great family, so I was one of the lucky ones, and I was able to get back to work. I feel so grateful to be working now.''
The darkness hit around a time of upheaval and, looking back, Kinevane can see he was trying to keep too many balls in the air - ''when you have a lot in your head and then a huge occasion comes along and one of them falls. There was a time when I thought I'd never be well again, that I wouldn't recover, and people don't.
''That's why depression is such a scary thing, because it makes you think there is no hope but there is. I suppose that's why I am trying to get rid of the stigma - especially for men - by talking about it.
''I don't feel any less of a man for having gone through a bad time. It's made me stronger and now I have the opportunity to give something back.''
In McGoldrig's case, his descent into madness begins with the suicide of his gay brother, who was the subject of much bullying growing up. Tortured by guilt for not having done more, McGoldrig hits the street and the bottle to anaesthetise the pain. If it sounds relentlessly grim, satire and irony are the antibodies that battle the toxins of pity and sentiment.
Monologues are punctuated by jokes, such as the one about a mental-health help line - ''if you are obsessive-compulsive press one … repeatedly''.
Silent has been touring Europe to critical acclaim for two years, and has won a clutch of awards, including two at the Edinburgh Festival Fringe, and has been described as ''riveting'' by the Sunday Times.
Kinevane, a well-known thespian in his own land who starred in Waiting for Godot and Dancing at Lughnasa before he turned playwright, visited New York in 2008, where he was shocked by the number of homeless people he saw and his own - and other people's - reactions to it.
In Dublin, he began to research the subject more, initially to understand his own prejudices, and eventually turned it into a manuscript. ''Some people might consider these people have a life and a story behind them but others don't. They just think 'loser'.
''I was fascinated by the idea about what drives people physically and mentally that low.''
He makes no apologies for proselytising; the script makes pointed references to Dublin's empty buildings while so many people are sleeping rough. ''I don't know what it's like in Australia but I do know that homelessness is everywhere. It's everyone's story.''
Almost five years after he started writing the play, Kinevane is still learning.
''At the start I thought homeless people all fitted into the same category but actually they don't.
''What I have discovered is that it is not always money that they need. To make eye contact with someone on the street is an enormous gift because it is recognition of another human being.
''I have also been amazed how quickly it can happen to people. It can happen to anyone.''
■ Silent is at The Lawler in Southbank Theatre, from February 7-10.