Lesbians, gay men and Welsh coal miners. They aren't, if you'll pardon the expression, the likeliest of bedfellows. And yet at one extraordinary moment of social and political history they came together, united by a common detestation of state authoritarianism in Thatcher's Britain, and a basic human decency.

That moment was the UK miners' strike of 1984, when a young gay activist named Mark Ashton (originally from Portrush, Northern Ireland) co-founded a group called Lesbians and Gays Support the Miners. Ashton died of AIDS in 1987, and it's a measure of the extraordinary bonds that rapidly developed between LGSM members and Welsh pit communities that a deputation of miners travelled to London for his funeral.

Micheál Kerrigan's new play Pits and Perverts traces the development of those bonds. Kerrigan lived in London during the 1970s and 1980s, and there is more than a trace of Ashton's passionate radicalism (and, no doubt, Kerrigan’s own) in Sean, one of four male characters whose interactions provide the bulk of the dialogue.

Sean, glimpsed briefly in the opening scene as a stuttering, insecure teenager in Derry~Londonderry, mutates into a chirpy, superficially confident gay man in London, where he shares a flat, and his life, with Gene, a music student from Canada. The pair's cosy domesticity is disrupted by the arrival of two striking miners, in London to march and demonstrate, whom Sean offers a couch to sleep on, in the cramped apartment that is Stuart Marshall’s period-sensitive set.

The miners end up staying weeks, and gradually the lives of the four intermingle, their attitudes developing from mutual incomprehension and wariness to a warm appreciation of what they have in common, as individuals trammelled by the monolithic forces shaping the social and political environment in which they find themselves.

Kerrigan's play successfully demonstrates how the little people of history can and do make a difference, even when momentous happenings are unravelling around them. At its heart is Sean's basic generosity of spirit, clearly evident in Conor Maguire's carefully considered performance. Maguire also effectively suggests Sean's underlying complexity: he is haunted by the memory of a friend shot dead on Bloody Sunday, and restless in his relationship with the long-suffering Gene, who palpably adores him.

Michael Johnston makes of Gene an endearingly sympathetic figure, a gentle foil to Sean’s impulsiveness and impetuosity. The two miners are more difficult to differentiate, but both Patrick Buchanan’s Rhys and Jason Davies’ David are keenly judged performances, both actors being particularly good at suggesting the warm vein of sensitivity underlying the surface gruffness of the characters, and the liberal amounts of manly facial hair they’re wearing.

With a colourful cameo from Orla Mullan as Gene’s upmarket student friend Candida, and genial, assured direction from Patricia Byrne, all the ingredients seem in place for Pits and Perverts to make a stirring impression. That the play is never quite as powerful as it might be is due partially to the way it’s structured, with frequent black-outs used to mark time passing, or provide the opportunity to shift props and furniture.

This modular approach, with most scenes kept deliberately on the short side, suggests a script more suitable for television, and makes it difficult to generate cumulative dramatic momentum. The stop-start nature of the narrative also militates against the actors filling out their characters more fully, and avoiding the slightly sketchy quality of the audience’s acquaintance with their inner lives and motivations.

Byrne’s direction does catch movingly the elegiac nature of the play’s conclusion, when the strike is called off by the miners’ leadership, and Rhys and David leave London, their year of financial hardship and personal sacrifice apparently fruitless. For Sean and Gene, the future is also uncertain. Will Sean depart to work in Nicaragua, as he has indicated he might do? Will Gene be able to stop him?

There’s a poignancy in these closing scenes that accurately and naturally mirrors the messiness and unpredictability of lived experience, and it’s to Kerrigan’s credit that he doesn’t seek to fabricate an inappropriately upbeat conclusion. As the back-projected words of the play’s epilogue remind us, history itself did not provide one: massive pit closures followed eventually, throwing 31,000 miners out of work, and rendering a once proud and vibrant industry moribund.

Pits and Perverts does its audience a service by resurrecting a little-known story from a generally ugly, inglorious period of modern British history, and showing that the basic instinct of ordinary human beings is more often than not to be kind and charitable to one another, if only their social and political circumstances will allow them.

Terry Blain is an arts journalist and cultural commentator, contributing regularly to BBC Music Magazine, Opera Britannia, Culture Northern Ireland and other publications.