Douglas Wager began talking about the plight of the American theater shortly after dinner. By 11 he was lamenting he paucity of new playwrights. By 11:30, he was cursing the Hollywood mammon. At midnight he was going strong on South African playwright Athol Fugard. An hour later, he was wondering why the American theater is incapable of such a precedent-shattering event as the Royal Shakespeare Company's "Nicholas Nickleby." Some time around 1:15, his wife, laid her head gently on the russet-colored sofa in their Falls Church bungalow and emitted a discreet yawn.

Glancing down at his watch, Wager suddenly looked as if he had been caught in an act of high treason, not merely an extensive discourse on a subject that enthralls him. without pausing, he made his hand into a gun, stuck his forefinger in his mouth, rolled his eyes and pulled the imaginary trigger. Bang!

It is this combination -- an utter devotion to the theater and a capacity to mock himself -- that people invariably cite when they talk of Wager (pronounced WAY-grr) and his steady rise at Arena Stage. Seven years ago, he was, in the words of a friend, "the lowliest of the low," a wide-eyed intern from Boston University whose job was to mop the stage every night before "Leonce and Lena." Today, at 32, he is Arena's associated director. He has set up and shaped its literary department. and he will be directing three of the theater's main-stage productions this season -- the South african drama "A Lesson From Aloes"; the Tom Lehrer revue, "Tomfoolery"; and the first revival in more than 50 years of the Marx Brothers' 1928 Broadway musical "Animal Crackers." Bang, indeed!

More importantly, he has become one of the closest professional confidants of Zelda Fichandler, Arena's founder and its producing director. A powerful and determined woman who does not easily relinquish her artistic prerogatives, Fichandler admits, "The fact that someone can come in here as an intern and end up an associate director makes me optimistic for the future. Otherwise, one feels like a mule -- the end of the line. Doug has taste and enthusiasm, and he's very important to me in that he supports and extends the whole idea of Arena as a continuing institution. We have an interlocking relationship. He senses when I'm tired, and I know when he's tired. I know when he needs someone to make a strong decision, and he knows when I need someone to come down hard on the other side."

A coworker puts it in slightly more prosaic terms: "Doug takes a load off Zelda's mind."

Increasingly, he has acted as the liaison between Fichandler and the members of the acting company, explaining artistic decisions and placating egos. He maintains much of the theater's continuing correspondence with hundreds of playwrights. If the final decisions are Fichandler's, Wager's influence in matters of play selection and casting has grown dramatically in the past few years.

"When I first came to Arena," he says, Rumanian director Liviu Ciulei "told me, 'If you have patience and don't feel you have to strive for that typically American flash-in-the-pan success, you can learn your craft here in a classical sense. But you'll have to stand in the shadow and th e hardest thing will be not letting your ego get in the way.' He was right, although there are times, even now, when my relationship with Zelda is like that of a mother and son, and I feel I'll never know enough, never be good enough, and that I'll have to leave or get swallowed up.

"There's no avoiding the fact that she's a woman with a very big personality," he says, tugging at the reddish-brown beard that gives him a passing resemblance to one of the Smith Brothers of cough drop fame. and I think we've learned to give one another the benefit of the doubt."

Wager and Fichandler first met at Boston University. He was a graduate student in theater; she was conducting a seminar, and she remembers him then as "brooding, a little uptight, sensitive and with a great desire to extend himself." Unsure of his intellectual abilities, he had grown up "a very Catholic young man" (his own words) in Coxsackie, N.Y., where his father was a prison guard. In high school, he identified with radical causes, played lead guitar in his own rock band and lost most of the hair on his egg-shaped head. "Actually, it was quite elegant to be losing your hair right in the midst of the antiwar movement, when everyone else was growing his," he jokes. "For a while I tried to comb a lingering strand across the top of my head, but it looked as it I was wearing a headset."

While at Boston University, he filed as a conscientious objector, although he was spared alternative service when the draft lottery stopped four numbers short of his. He also switched majors from chemical engineering to theater. "What I discovered about the theater -- and why I will always stay in it," he reflects, "is that it speaks directly, viscerally, to people like my father, who never graduated from high school. It can elevate him to a level of thought and emotion that he may not be able Ui," he flung a skittish actress on stage nightly for her big death scene at the hands of a firing squad. "I asked if that was because she was supposed to look as if she were being propelled from offstage," he remembers. "'No,' I was told. 'It's because she won't go on otherwise.'"

He was backstage handling props for "The Madness of God" one night when the elderly lead, Joseph Wiseman, collapsed after the first act. Wiseman's understudy in the Jewish drama had just arrived in town and didn't know the blocking, so "they rushed me to the dressing room, put white shoe polish in my beard, and 10 minutes later I was sitting in the middle of the Arena with a script in one hand, the Talmud in the other. When the lights finally went out, someone had to come get me. I didn't know how to find my way off the stage in the dark."

His backstage chores rapidly escalated in importance, although for "Saturday, Sunday, Monday," an Italian comedy that requires an actress to whip up a full meal on stage, he had to give cooking lessons to Arena's leading lady. "She didn't know how to boil water," Wager recalls. "On principle, she didn't own any pots and pans. She didn't even like the 'sound' of water boiling."

By 1977, he had been moved "upstairs," where Arena's policies are shaped and Fichandler's word is, if not law, at least a formidable factor run the series and even direct several of the offerings.

"Doug has always been tremendously supportive in bringing writers along," says playwright Richard Nelson. "He has a huge amount of patience, and knows how to mediate artistic differences. In meetings, he keeps everything relaxed, with a joke or a pat on the back or a bit of self-deprecating humor, and just an extraordinary amount of caring."

But his growing importance stems from the dozens of hours a week he spends thrashing out ideas with Zelda Fichandler; and functioning as a gadfly and sounding board. Mostly they confer in her office, where he pulls an orange chair up to the edge of her desk. But they can run into one another in the corridor and end up having a 45-minute conversation on the spot."If there is one overriding esthetic here, it's that Arena is a theater which reflects the connection between thought and passion," he explains. "Man is both a thinking creature and he's a passionate animal, and the plays we look for are those that explore this synthesis -- comically, tragically, ironically.

"Zelda infuses her extraordinary intellect in all the work that is done here. I don't come from the intellectual side of the spectrum, however. What I enjoy most about life is how people behave emotionally with one another, and how that often translates itself in nonverbal language.as they contribute to a continuing dialectic Fichandler finds crucial for her theater's well-being. "The more assertive someone is, the more helpful it is to me," she claims. In the past, Wager has pushed strongly for such plays as Sam Shepard's "The Curse of the Starving Class," Ron Whyte's "Disability," David Hare's "Plenty," Albert Innaurato's "Gemini," David Mamet's "American Buffalo" and Anthony Giardina's "The Child," which is not to say they wouldn't have been done otherwise. Still, he is the spokesman at Arena for "the more stylistic, nonrealistic world of new playwriting." He confesses that lots of his ideas don't make it to first base, but some -- a musical adaptation of "Elmer Gantry" for next season, for example -- are already being coaxed into being.

For the public, however, Wager's most visible achievements are the productions he has directed in recent seasons. While he never solved the thorny problems of "The Child," last spring's drama about the emotional fallout of an abortion on a young married couple, he brought great eclat and humor to the revivals of "You Can't Take It With You" and "The Man Who Came to Dinner," and he is, in the opinion of many, one of the best directors of 1930s farce in the country.

"A Lesson From Aloes," a fierce drama about three South Africans, two white, one black, who have been psychically scarred by that country's apartheid pol" icies, calls upon a more introspective side of his talent. The show opens on Nov. 11, and at rehearsals, he hovers, eagle-eyed, on the lip of the Kreeger stage, hugging himself as if for warmth. Abruptly, he takes actress Halo Wines aside for a long confidential discussion. "Aloes," in one respect, is a play about people hiding from one another, and part of Wager's directorial approach is to foster secrets with each of the cast members.

"Doug doesn't try to accomodate you," explains Stanley Anderson, also in the cast. "Some directors will say, 'Yeah, that's sort of it,' and let things pass. Doug's attitude is 'Don't settle! What you're doing is okay, but let's see what else there is.' He's always throwing out alien images at you, and either you have to deal with them, or reject them and know why you're rejecting them. I find that very useful."

This summer, Wager abandoned what his friends describe as a reasonably swinging state of bachelorhood to marry Cary Spear, a 32-year-old editor for the Congressional Research Service. ("I felt I had to make a deep commitment to something other than Arena Stage," he says." A redhead whose pre-Raphaelite features belie the exuberance of her personality, Spear has aspirations of her own to be an actress.

Already she has played several bit parts at Arena, and is understudying the female role in next month's "Aloes." Wager admits that it makes for a delicate situation and that, given his position, he cannot always be as unrestrained in his encouragement as he would like. "I tell him that if I were trying to sleep my way into the theater, I certainly wouldn't have stopped with him," she counters gaily. "I'd be giving Roger Stevens a big run for his money right now." Despite the manifest contentment of the newly married, Wager confesses he sometimes feels trapped "trying to satisfy the expectations of two demanding women. I owe them both a lot."

Fichandler dismisses the notion that plagues Wager in his worst dreams -- namely that he is merely one of her puppets. "This place doesn't work by decree or edict. It's not as centralized as you might believe," she says. "I don't limit or circumscribe the contributions of other people. What I think they have to do is push up against a very strong personality in order to take up the space they have to take up. And whatever space they can take, they are welcome to it."

She pauses. "Doug deals very gracefully with actors and he has a real feeling for alternatives. Running a theater is filled with anguish. Doug has relieved a lot of my pain."