Director Peter Sellars, a risk taker by nature, has taken his biggest risk yet with an updated production of Sophocles' tragedy "Ajax," which opened Saturday night at the Kennedy Center's Terrace Theater.

His casting decisions are pure audacity. His staging is even more defiantly unconventional than it was for "The Count of Monte Cristo" and "A Seagull." And his passionate belief that the theater must burrow into the conscience of the community has never run quite so deep.

But if "Ajax" is a bold and brazen gamble, it is also, I fear, one that pays highly erratic dividends. Those who have heretofore been dismayed by the eclecticism of his productions will be positively flummoxed this time. When public faith in the American National Theater is running low and Sellars sorely needs to prove that he is not merely the intelligentsia's darling, "Ajax" can only further alienate the popular audience he desperately needs to stay in business.

*Its strongest asset is an astonishing performance in the title role by deaf actor Howie Seago, who renders his lines in sign language. The actual words are uttered by members of the chorus, soldiers in battle fatigues, talking at close range into microphones. Seago's rugged face is a map of primal emotions and his hands speak with thundering power. Here is man very much as the Greeks viewed him -- strong and proud and ultimately helpless before the gods.

Sophocles' play chronicles Ajax's ignominious descent into madness and shame; Sellars sees it as a latter-day inquest into the military in a country rapidly drifting to the right. The country is the United States -- sometime in the near future, just after a triumphant campaign in Latin America, although the production also seems to be concerned with the divisive legacy of Vietnam. The action is set simultaneously in the Pentagon, where Ajax's questionable behavior is under investigation, and on a beach, where he expires by his own hand.

Playwright Robert Auletta has revised the script with topical references and barracks jargon, although much of the original play shines through. So we get a purposefully mixed bag of references -- to swords and shields in one breath, automobiles and baseball in the next.

As Sophocles and legend had it, Ajax, furious at not having been awarded the dead Achilles' armor after the Trojan War, set out to massacre his fellow Greek generals. The goddess Athena, however, intervened, driving Ajax mad so that in a temporary fit of delusion he slaughtered a field of cattle instead. The original play examines his disgrace, his suicide and the heated feelings of his survivors, who must decide whether to give him an honorable burial or let him rot in the sun.

Calling Ajax's plight "a national security problem of the highest order" does not entirely disguise the fact that much of it resists modernization. To the extent that Menelaus, Odysseus and Agamemnon -- once Ajax's comrades, now his enemies -- have assumed the titles and trappings of Pentagon brass, they have lost a lot of their reality. Indeed, Odysseus' vow that if ever he meets Ajax in hell, "it will give me great pleasure to kick him in the [private parts]" is patently laughable.

Tecmessa, Ajax's foreign-born wife, is played by Japanese actress Lauren Tom -- the implication being that Ajax met her in Southeast Asia. Ajax himself, we are told, is part Sioux. And the traditional messenger (Ben Halley Jr.) has been transformed into an angel with six-foot wings, who at one point gravely intones a black spiritual. Apparently, however, Athena (Aleta Mitchell) still retains her status as a goddess, even though she presides over the courtroom procedures in a silver lame' dress.

It makes for a curious hybrid, reminiscent by turns of "The Gospel at Colonus," Robert Wilson's meditative theater pieces, the experiments of the Wooster Group with its emphasis on electronic technology and the efforts of the Suzuki Company of Toga to fuse Japanese and western traditions in the crucible of Greek tragedy. Sellars, who has a mind like a sponge, is not afraid to borrow. But the many layers of "Ajax" never acquire a dramatic coloration of their own. The stark human dimensions of Sophocles' tragedy are concentrated largely in Seago's performance.

His first appearance is a shocker. A shroud is whipped from a glass booth partially filled with bubbling red blood. There, splashing in the plasma and emitting guttural cries, is the demented Ajax. In its way, the sight is as powerful as the sickening, blood-spattered finale of "Taxi Driver." When the action switches to the beach, Sellars rings up the corrugated metal doors of the Pentagon, and a river of water pours down the raked stage. The superimposition of one locale on the other makes for a nightmarish double exposure.

The rest of "Ajax," however, is less immediate. Long soliloquies are whispered (or occasionally bellowed) into microphones by the actors, who are seated either on the witness stand or at conference tables. Sometimes they talk in the dark. Athena makes her entrance through the auditorium, her breathy voice relayed over the loudspeaker system. Mitchell has the figure, at least, of a goddess.

Tom captures the fear and bewilderment of Tecmessa, but Khin-Kyaw Maung can't seem to get a grip on the role of Teucer, Ajax's loyal half-brother. And while Warren Manzi, Charles Brown and Samm-Art Williams play the hard-bitten Pentagon officers with appropriate macho swagger, the incongruities of Auletta's script make them look silly.

"Ajax" runs nearly two hours without intermission. Then, following antique tradition, Sellars gives us a brief satyr (burlesque) play, intended to end the evening on an irreverent note. Since all but one of the original Greek satyr plays have disappeared, Sellars has commissioned his own -- "The Bob Hope War Zone Special" by George Trow.

Besides Manzi's impersonation of Hope, which misses by a country mile, it features such characters as the king and queen of Sweden, a Washington Redskin, Miss Teenage American Mother, a couple of cheerleaders and three young men in bikini briefs. Just what it is all about I couldn't begin to tell you. But the antics are mortifyingly unfunny.

"Ajax" may represent an honest, if flawed, attempt to penetrate the mysteries of Greek tragedy. "The Bob Hope War Zone Special" resembles a frat show hatched in a moment of alcoholic stupor. Correspondingly, the cast performs it as if it were just another humiliation in the degrading ritual of hazing.

It may be pure coincidence that while "Ajax" is playing at the Terrace, a revival of Herman Wouk's "The Caine Mutiny Court-Martial" (another play about madness and responsibility in the military) is entrenched in the Eisenhower. The one is as thuddingly old-fashioned as the other is painfully esoteric. Is there no middle ground?

The Kennedy Center, it would seem, is developing a dangerously schizoid personality.

Ajax, adapted from Sophocles' play by Robert Auletta. The Bob Hope War Zone Special, by George Trow. Directed by Peter Sellars. Sets, George Tsypin; costumes, Dunya Ramicova; lighting, James F. Ingalls. With Charles Brown, Ben Halley Jr., Warren Manzi, Khin-Kyaw Maung, Aleta Mitchell, Howie Seago, Lauren Tom, Samm-Art Williams. At the Kennedy Center Terrace Theater through July 5.