IN HIS harrowing drama "Dorothy," Irish playwright Graham Reid turns a suburban home into a battlefield, a microcosm of the violent throes of Northern Ireland. At New Arts Theater, it is a forceful and fearsome wide-awake nightmare.

Dorothy Williams is a frustrated middle-class housewife afraid she's missing out on life's adventure: Even the violence visible from her window overlooking burning Belfast seems romantic. Left alone with her drinks and country music in her isolated suburban dream home, Dorothy tries pathetically to get the attention of her husband and son but only succeeds in alienating them.

Reid's portrait of Dorothy and her marriage is thoughtful and complete enough to stand on its own as a play. But things quickly take a horrific twist, and Dorothy gets more excitement than she bargained for. With her husband and son away on a business trip, Dorothy unwittingly allows three thugs into the house, igniting an ugly evening of terror in which she is beaten and gang-raped.

Changed irrevocably by the nightmare, Dorothy burns her sexy wardrobe and accepts the solace of her self-righteous sister. But the trouble is far from over -- vengeful and bitter, her husband and son plot retribution, and the vicious cycle continues.

Dorothy and her family can be seen as stand-ins for ravaged Ireland herself, and though the Williamses have taken to the hills to escape "the troubles," Reid's play makes it clear that there is no place to hide from the sectarian and class conflicts.

Dorothy contains graphic violence and sexual situations, and director John Neville- Andrews doesn't flinch from the material. Within set designer Michael Layton's pink and placid suburban setting, Neville-Andrews creates an atmosphere of unbearable tension, urging performances so physical you may fear at times for the safety of the actors.

As Dorothy, Mary Ellen Nester is never less than convincing, capturing this very real woman's biting, desperate wit, her pathetic loneliness and her spiteful defiance in the face of her tormentors. Marty Lodge plays Mike, the slick, softspoken leader of the creeps, with chilling control. And in addition to boasting this troupe's best brogue, Michael Wells underplays effectively as Dorothy's teenage son, concerned for and repelled by his mother.

DOROTHY -- At New Arts Theater (at All Souls Unitarian Church, 16th and Harvard streets NW) through May 3.