Ireland, Great Britain and the USA have been tangled in a see-saw relationship for the better part of two centuries. There have been appalling wrongs committed as well as acts of extreme generosity. Heroes and villains, traitors and patriots, victims and quasi-conquerors – they’re all natural products of this razor-wire knot.

Richard Bean’s new play is concerned basically with Irish Americans in the period 1972 to 1999. There’s support for the IRA and the PIRA, some of it vocal and emotional, quite a lot of it more deadly. Most of the action takes place in a Bronx apartment over this period. The title character is David Costello (Finbar Lynch), the senior IRA man but also an American citizen who fought in Korea and Viet Nam.

He’s a thinking man with a conscience, and Lynch brings out all the contradictory facets of his character in a characterisation which is ultimately moving as well as strangely heroic. Of the other men in his cell, the most interesting is Michael Doyle (David Ricardo-Pearce), owner of the flat, a Protestant Irish nationalist who is changed, even warped, by offering his apartment as a safe-house.

Altogether simpler in his needs and expressions is fireman Ruairi O’Driscoll. Rory Keenan makes him sympathetic in his jumble of aspirations, ranging from bedding attractive girls to feeling part of an important political movement – provided that he doesn’t have to kill anyone. There’s also a pair of “hard men” – Youssef Kerkour as the brutish policeman Tom Billy Coyle and Fred Ridgeway as hit-man Frank McArdle.

This is not a culture into which women fit comfortably, other, that is, than in traditionally subservient roles. Stephanie Street is Karelma, a Puerto Rican immigrant and Claire Rafferty plays Elizabeth, an IRA high-flyer deeply resented by many of her older male colleagues. The intensely concentrated production is by Max Stafford-Clark, a trademark piece of direction. Tim Shortall’s set is suitably drab with its green walls suggesting fungus rather than a spring awakening.