DA by Hugh Leonard; directed by Melvin Bernhardt; scenery by Marjorie Kellogg; costumes by Jennifer von Mayrhauser; lighting by Arden Fingerhut

With Barnard Hughes, Tom Cawley, Helen Stenborg, John Wylie, John Didrichsen, Dennis McGovern, Victoria Boothby, Laura Hughes and David Leary.

At the Eisenhower Theather through May 10.

"Da" has a lot going against it. It is about a son coming to terms with his parents -- perhaps the theater's most overworked theme-of-the-moment. One of its principal characters, Da himself, is a ghost, a device that has been growing steadily less acceptable for centuries now. And besides being a ghost, he's a windbag. An Irish windbag yet!

But as last night's opening at the Eisenhower Theather reaffirmed, craft and imagination can overcome no end of obstacles. Yes, "Da" (an Irish-ism for "Dad") is another of those nostalgic, heart-warming plays the Kennedy Center delights in supplying, but it performs its mission honorably -- having justly won, among other honors, the 1977-78 Tony Award as Broadway's best play (coincidentally, the play received its American premiere at the Olney Theatre in 1973).

And it has a sensational performance by Barnard Hughes in the title role, a blithering, blathering, incorrigible old man who sees the world through inch-thick rose-colored glasses.

"If you ran into him with a motorcar," says his ever-exasperated son Charlie, "he'd thank you for the lift."

To prove the point, after 54 years' service as a gardener to a well-to-do local family, Da goes expectantly to a final interview with his employer's wife, hoping for at least the same 100-pound going-away gift the cook got.Instead, he gets 25 pounds sterling and a memento of the San Francisco earthquake -- a melted glob of "30 or more spectacles fused together by the heat of the fire."

His only outward show of disappointment is a momentary silence, followed by a somewhat quieter-than-usual "Thank you very much, ma'am." His wife, furious with him for behaving so meekly, refuses to talk to him for a week.

Da is the sort of character playwrights generally use for comic relief, not as a central subject. But Hugh Leonard is interested in this man for the very quality that might make other writers give him short shrift -- his docility, his senseless optimism, his unfailing willingness to accept his sorry station in life.

Seen through the super-critical eyes of his adult son, Da is, like many a parent, asking to be comprehended in his entirety. In the meantime, he will go on being a ghost and a nag.

While the father/son relationship is at the heart of this play, Charlie's mother, far cooler and more strong-willed, is also a richly written and, by Helen Stornberg, a richly acted character. When her son asks her to explain her choice of a husband, she answers that it was an arranged marriage: "A body's not put into the world to pick and choose and be particular," she says. Besides, when this life is over and a person meets St. Peter at the gates, "it won't matter whom you married."

It is hard to resist supposing that "Da's" picture of a young man growing up during World War II in an unnamed Irish town must be autobiographical. uCharlie, the narrator/hero, is a playwright (although, God be praised, that aspect of his life is revealed and exhausted with all possible speed). More to the point, even the funniest and most farfetched scenes -- those, for example, depicting Charlie's frantic efforts to lose his virginity with the local tart, and his early career as a clerk to an eccentric, curmudgeonly employer -- have the dizzy ring of truth.

An interesting, if peripheral, point is the importance of America and things American in Irish life as Leonard depicts it. Charlie's dim-witted friend Oliver is a proud graduate of the Dale Carnegie school of self-confidence, and both of them daydream of Veronica Lake, Gary Cooper, Gene Autry and Maria Montez (in "Cobra Woman"). This is 1944 or so, with Ireland neutrally standing apart from the war -- but when one young Irishman bids another goodbye, he explains: "I must be riding the trail to the old hacienda."

"Da's" most notable virtue may simply be that it is, unmistakably, a piece of theater, exploiting and even milking a host of purely theatrical gimmicks.

Charlie at 40 and Charlie at 18 occupy the stage simultaneously, for example, with the elder criticizing his younger self's awkward way with women, and the younger voicing disappointment with his "ordinary" apearance-to-be. Resorting to an even hokier device, Leonard has Charlie try to be rid of his father by slamming a door on him -- but Da merely steps around the door and keeps right on haunting and chattering away.

If someone told you he was writing a play like this, you'd put a wise hand on his shoulder and suggest he consider a career in insurance instead. But if anyone gave Leonard any such counsel, he clearly paid no mind. And with "Da," he has had the last laugh -- and plenty of others, besides.