SANTA MONICA, CALIF. -- It was 9:30 p.m. and I was watching an ensemble of talented and famous American actors rehearsing a radio drama about a crucial moment in the history of the newspaper that employs me.

Right away, I realized I had made a mistake. I should not have been there.

Susan Albert Loewenberg, producing director of L.A. Theatre Works, which is bravely attempting to revive American auditory drama, seemed to sense my problem. "Close your eyes," she said. "Then you can get a better sense of it."

Too late. I had already seen Howard Hesseman, in the role of then-Washington Post board Chairman Fritz Beebe, take his seat with Ed Asner, Marsha Mason, Ed Begley Jr. and a host of other workaholic Hollywood actors willing for little money to present "Top Secret: The Battle for the Pentagon Papers" to a national radio audience (including WETA, 90.9 FM, Saturday from 2 to 4 p.m.).

Beebe, I knew, was a distinguished New York attorney and Ivy League graduate who rarely had even his tie askew. Hesseman, made famous by his role as the perpetually zonked disc jockey Johnny Fever on "WKRP in Cincinnati," had the voice right -- soft, cultured, precise. But there in a meeting room of the Guest Quarters Suite Hotel just off the Santa Monica Freeway I was seeing as well as hearing Hesseman, and could not shake the jarring impression of Beebe's words emerging from the mouth of someone who looked like a derelict dragged off of Venice Beach -- a three-day growth of white stubble, shoulder-length hair and a long black coat that covered God knew what underneath.

"Top Secret" -- vividly written and full of the paranoia and media-vs.-government bile of the Nixon years -- includes portrayals of several real people I knew well. It was impossible, with my eyes open, to make the rounded, sweat-shirt-clad figure of Asner fit my image of Washington Post Executive Editor Benjamin C. Bradlee, or reconcile the bald, intense visage of veteran Post Pentagon correspondent George Wilson with the actor playing him, the tall, wisecracking, dazzlingly blond Begley.

So I left as soon as I could, preferring to listen, and listen only, to an intriguing effort to find space for serious playacting on car radios vibrating with news and rock contests.

Loewenberg's L.A. Theatre Works, in partnership with Santa Monica College-based public radio station KCRW, has already done a 14 1/2-hour reading of Sinclair Lewis's "Babbitt," with Asner in the title role, and received incandescent reviews. "Don't you get sick of British voices on NPR and PBS, particularly when they're doing our material?" wrote Los Angeles Times theater critic Dan Sullivan in a flag-waving tribute to the production. The company has brought "The Crucible," "Once in a Lifetime" and other plays back to radio, and Loewenberg sees this weekend's Pentagon Papers drama as a way to tie the revival to what listeners are hearing when they switch over to the all-news station.

"I was sitting and watching the gulf war coverage," she said, "all the interaction between the press and the official briefers, and watching the incredible hostility." It triggered a memory of a play sent her by Los Angeles attorney and political activist Geoffrey Cowan and former Post reporter and Oakland Tribune Executive Editor Leroy Aarons.

Their drama, first written in 1983, recounted a tense day in Bradlee's Georgetown living room in June 1971 as The Post decided whether to risk defying government objections to publication of former defense secretary Robert McNamara's secret history of the Vietnam War. To Loewenberg, it seemed perfect for radio at a time of rabid debate over pool reports and CNN broadcasts from Iraq.

During the rehearsal, if I closed my eyes tightly enough, I could see that she was right. I joined The Post the day the New York Times published the first story on the Pentagon Papers. I thought I had had my fill of what had been in my life countless discussions of the pain of being beaten on such a story, and the excitement of seeing more leaked documents in my paper -- in the face of possibly ruinous government retaliation -- when the courts silenced the Times.

"I'll tell you what the rush is," barked Asner, playing Bradlee, at rehearsal. "For three days the Times has beat the living bejesus out of us."

The clash of foul humor, frantic competitiveness, financial uncertainty and moral courage came back in the play with full intensity, and spared few of the principals their best and worst moments. Aarons interviewed all the people involved, and he and Cowan distilled several interesting personalities into a few characteristic sentences.

Mason, as Post publisher Katharine Graham, caught the hesitancy of an executive listening to strong men suggesting her paper would go down in flames whichever way she decided. Robin Gammell, familiar to some as an occasional judge on "L.A. Law," perfected diplomatic correspondent Murrey Marder's bulldog persistence. Nan Martin's throaty version of editorial writer (and now Editorial Page Editor) Meg Greenfield was eerily close to the original, though the two have apparently never met.

Director Tom Moore, who did both stage and screen versions of the Pulitzer Prize-winning " 'night Mother," attempted during rehearsal to keep the government side also true-to-life. He cautioned Gerrit Graham on his reading of Justice Department attorney Robert Mardian. "Even if he is an SOB, make him a sophisticated SOB, like {Nixon aide John} Ehrlichman," Moore said.

"What's the matter?" Graham said with a grin. "Can you hear me twirling my mustache?"

The cast, full of politically attuned actors who said they were fascinated by parallels between 1971 and 1991, worked late into the night. It included Robert Foxworth as Post Assistant Managing Editor Ben Bagdikian, Philip Abbott as veteran correspondent Chalmers Roberts, Stacy Keach as Attorney General John Mitchell, Joe Spano as presidential Press Secretary Ron Ziegler, Harry Shearer (a humorist who does many voices on "The Simpsons") as President Nixon, Harris Yulin as Henry Kissinger and James Whitmore as Judge Martin Peel. In a last-minute change that producers said had nothing to do with Hesseman's rehearsal costume, the Beebe part was given to Hector Elizondo, and Hesseman played a fictionalized Post attorney, Brian Sullivan.

Cowan, who recently chaired a mayoral committee drafting a new ethics law for Los Angeles, said the idea for the play came to him as he was preparing a case study on the Pentagon Papers for a class in communications and media law he taught at UCLA. He and Aarons, a former Post bureau chief in Los Angeles, sharpened the dialogue and added material from closed Pentagon Papers hearings obtained by New York Times columnist Anthony Lewis.

Aarons said professional dramatists told them, "If you want to do it for the stage you have to fatten the drama and enrich the characters." Eventually they produced a version in which all the characters were fictionalized and some romantic elements added, but it was an earlier version that Loewenberg read and decided to produce.

A panel discussion including the real Bradlee, Wilson and other journalists followed the play, broadcast live Thursday night on most major market National Public Radio stations. National Public Radio is not providing the panel discussion to stations such as WETA-FM, which chose to broadcast it later.