Hampstead Theatre, London

THE GATHERING storm of Druid Theatre Company’s phenomenal cycle of three Tom Murphy plays is almost overwhelming. But, like the tour that Conversations on a Homecoming, A Whistle in the Dark and Famine will undertake – opening in Hampstead Theatre as part of London 2012 Festival and destined for New York before returning to Ireland – it is a riveting, shattering and deeply necessary journey.

Beginning in a Galway pub in the 1970s, where Conversations attempts to rekindle idealism in an Ireland of curdled promises; slipping back in time to a cramped 1960 Coventry home where Whistle’s violent Mayo men establish territory while tearing themselves apart; and resolving, finally, in the blight-stricken Mayo village of Famine’s Glanconnor in 1846, the complete cycle offers a retrospective of both Tom Murphy’s career and an Irish psyche scarred by the legacy emigration.

As a theatrical event, though, its emotional effect is as immediate as a heated argument, or a wallop to the chest.

Director Garry Hynes’s epic project has a headline timeliness, but her agenda, served by a superlative ensemble, is to probe much deeper, realising the shaping forces of pride and humiliation, drink and violence, acquiescence and defiance.

In their delivery of his muscle and musicality, Druid remind you that no one has articulated the legacy of dispossession as eloquently or unflinchingly as Murphy.

As Marty Rea’s returnee Michael speaks of beauty and ideals to his hectoring “twin” Tom, played with stentorian gravitas by Garrett Lombard, you appreciate that the only difference between a romantic and a cynic is disillusionment – the two combined, says Rory Nolan’s Junior, “might make up one decent man”.

But on one booze-warped night in a bar called the White House, decency is in short supply, while past, present and future collapse into telling repetitions: the moithered movements of Marie Mullen’s Missus, the strained simpering of Eileen Walsh’s Peggy and the materialism, affectation and drunkenness of Aaron Monaghan’s auctioneer Liam are all as amusing as they are heart-breaking.

A Whistle in the Dark, conspicuously revised by Murphy for this production, holds that despair in a clenched fist. Niall Buggy, brilliantly combining brutality and feebleness as the frustrated tyrant Dada, would sacrifice the future of his youngest son Des (a remarkable Gavin Drea) for the sake of establishing dubious pride.

Rea, as the conflicted elder brother Michael, Walsh as his beleaguered English wife and Monaghan as the unnerving, violent Harry again excel and, while Hynes serves the play’s still shocking climax with the heavy drag of furniture across Francis O’Connor’s wooden boards, she ensures the play’s more stunning wattage flows directly between them.

As Brian Doherty’s doughty village leader John Connor pulls his failing crop from the earth to inspect it, an effort to trace the seeds of demoralisation back to Famine might seem reductive: the potato did it. But while Murphy’s Brechtian structure similarly uproots historical injustice, Hynes’s daring staging issues a more vital, contemporary warning. Fully exposing O’Connor’s allusive backdrop of corrugated, rusted iron, under Chris Davey’s lights, while Joan O’Cleary’s costumes allow their own bracing anachronisms, its most extraordinary scene has the bodies of the starving stretch and contort in the background (under David Bolger’s considered movement direction) while the Relief Committee fidgets towards a blunt ultimatum: emigrate or perish.

These plays may be seen separately, giving the density of thought and emotion in Murphy’s work time to unravel, but viewed together the works abound with rewarding echoes and insistent, pressing whispers, threaded through with striking visual motifs and the illuminating torch of extraordinary performers. Druid’s collaboration with Murphy is a staggering achievement and here it lets the plays speak to us as urgently as they ever did.

Until June 30th at Hampstead Theatre; July 5th-14th Lincoln Center Festival, New York; July 23rd-28th Galway Arts Festival; September 11th-29th Irish tour; October 2nd-13th Dublin Theatre Festival