David Berry makes his playwriting bow with a shattering, intense drama, "G. R. Point," which is having a stirring pre-New York production at Center Stage through Feb. 4.

The dominant player is Michael Moriarty who, when the role suits him, can be very, very good and, when it doesn't, can be insufferable -- as was the case when he appeared with Jason Robards and Zoe Caldwell at the Eisenhower in "Long Day's Journey into Night." This time, as in his awardwinning "Find Your Way Home" (stage), "Bang the Drum Slowly" (film) and "The Glass Menagerie" (TV), Moriarty is superb.

So is Berry's drama about a unit of American soldiers in Vietnam. From time immemorial war plays about units of men have represented classes and types artificially joined. But here Berry is reaching into uncommon philosophical probing which distinguishes "G. R. Point" beyond the ordinary.

Unquestionably, the raw language and scenes will repel some, but the joltingly specific words, which can engulf even the most civilized, are vital to Berry's statement.

He is recognizing that the cruelty of the mind can be as destructive as bombs. Determined to maintain the generations of civilized dispassion 300 years of New England living has given his family, Micah achieves murder through mental cruelty.

A striking feature of plays about the Vietnam war has been the reference to and the showings of mangled bodies. David Rabe's _ietnam trilogy made the point. So did the first effective play of the New Playwrights' Theater, "The Return of Capt. D. B. Amatucci," by T. J. Camp III, about a Graves Registration unit. The images result from those "body counts," which dominated the 1960s.

To a Graves Registration Point in a Vietnam waste comes a refined Amherst graduate whose major correspondent is his mother. He is determined to write her unflinching descriptions of what he sees and does. Veterans in the unit, one in particular, urge him to do no such thing.

"Back in the World," Zan argues, gory details will be meaningless. "Back in the World" becomes a recurring phrase, accenting the unit's apartness from everything its members have known before. There is a unity against "back in the World," which doesn't understand anything about this madness. After his first night attack, Micah is shattered to discover that he had gloried in the gore, that his reaction had been orgasmic.

Friend Zan, the one man who understands him intellectually, is killed without knowing of Micah's respect for him. Back in Maine, Micah's specific descriptions "have killed her brain cells one by one" so that his mother dies of a stroke. Berry's point is that Micah's unrecognized rage has been directed against a loved friend and his mother. The theme goes back to Socrates: "Know thyself."

On Peter Larkin's stunning set of parched earth and with strong atmosphere from Kirk Nurock's sound score design, William Devane has staged a splendid ensemble cast. Moriarty's Micah is superbly conveyed. So, among others, are the unique portraits of Michael Jeter, as one of the men, and Lori Tan Chinn, as a native.

Introduced at Connecticut's O'Neill Center, the plan is to follow Baltimore with a New York production. The sooner the better.