Hal Holbrook is nestled into a chair in the administrative offices of the Shakespeare Theatre in Southeast Washington, but he's really somewhere outside Dhahran, Saudi Arabia.

The rest of the cast of "The Merchant of Venice," which opened Tuesday with Holbrook in the role of the reviled moneylender Shylock, is rehearsing across the street on this Saturday afternoon. For Holbrook, though, it's 1960. He's 35, the beatings and abandonments of his childhood are still vivid in his mind, and he's in a big car that's racing across a desert highway at 80 miles an hour. Next stop: some forgotten little town where he'll perform his one-man show about Mark Twain, which hit it big in the United States the year before.

The driver, he says, is "a madman. Everything has to get out of the way because he's going to run it over. And there up in the distance, I can see this tall, white, thin, sticklike figure of a man with a headdress, starting to cross the road in a very slow, measured and stately pace."

The figure never even looks to see whether his way is clear. The driver keeps his foot on the accelerator. The way Holbrook figures it, the man should be dead center of the car when it hits him . . . in about three seconds.

"Stop!" Holbrook screams. The driver locks up the brakes, tires screeching. "We stopped within inches of this ancient man's legs, and only then did he stop and turn his head. He looked straight into my eyes. And I saw 2,000 years of implacability. Totally unmoving implacability. And then he looked away and very slowly continued across the road."

Holbrook leans forward now, narrowing his own heavy-lidded blue eyes, as if looking through a rifle scope. It's 1999 again. "All kinds of images assail an actor's mind," he murmurs. "But that one keeps coming back to me. Because there's something in Shylock that is in that man's eyes."

Shylock the hated and hating Jew, often played in Shakespeare's time for ugly caricature: Holbrook, not surprisingly, sees a more complicated character. He's not the first actor to sense that, nor the first to use an indelible memory as a template for his character. But when he later speaks about his own childhood, you start to understand how a man can instantly recognize implacability in another. And use it.

Though there's a nice symmetry in Holbrook's appearing in the Shakespeare Theatre's season closer--his wife, Dixie Carter, appeared in the opener, "A Woman of No Importance"--he seems, at first glance, an odd choice for Shylock. Nothing he's done, certainly in film and television, immediately suggests he can reveal the deep emotional scars that harden over a lifetime of persecution such as Shylock has endured, and that disfigure a man's soul so much that he becomes complicit in his own undoing.

The first actor to portray Shylock with any kind of humanity was the great Edmund Kean, who made his London debut in the role in 1814, astonishing audiences with his passionate, fiery style. "To see Kean," Samuel Coleridge said, "is to read Shakespeare by lightning." To some extent every actor since has worked in Kean's shadow. Holbrook has studied the record of that seminal performance, as well as those of many others who later attempted the role. He's also heavily researched the history of Renaissance Jews.

Still, at 74, his hair and beard a wild, silvery shock and grizzle, Holbrook is of course best known for his stage impersonation of Twain, to which he brings a winning mix of wit, outrage and vulnerability. He's also won five Emmy Awards for roles in contemporary television drama.

Yet Shakespeare is hardly a stranger to him. While "Mark Twain Tonight!" began as part of an honors project he was involved in as a student at Denison University in Ohio right after World War II, Holbrook and his first wife started out in 1948 by hitting the school assembly circuit in the Southwest. They drove more than 30,000 miles, performing 307 times over the course of 210 days, staging a two-person revue of Shakespearean characters (with an occasional Twain monologue sandwiched in) "to kids who only cared about country music and Roy Rogers. It was like playing to a bullring sometimes."

Later he knelt--briefly--at the altar of the Method, studying for three months in New York under Uta Hagen. "It scared the hell out of me! All these people leaning against the wall and thinking before they went onstage. They all seemed to know more than I did. It really intimidated me. It was only after leaving the class that I began to understand the good of it, which is to try and get in touch with your real self, your true self."

He spent the next five years developing and refining Twain into a full show, which debuted off-Broadway to rave reviews in 1959. By 1966 he'd taken it on Broadway and won a Tony Award for it. Television and film roles were also coming his way, leaving him little time for stage work other than Twain. About 10 years ago he started feeling it was time to come back to the boards and the Bard. Acting for cameras had distracted him from assaying great roles such as Richard III and Hamlet. If he wasn't careful, he might find himself too old even to play Lear--which he finally did in 1990 at the Roundabout Theatre in New York.

The next year he played Shylock--in a modern-setting production of "Merchant" at San Diego's Old Globe Theatre. Despite some warm reviews for his performance, Holbrook wasn't happy: He felt the updated setting with its updated manners had blunted not just Shylock's character but also the play's sharp antisemitism.

Several years afterward, he rang up Shakespeare Theatre Artistic Director Michael Kahn, whom he'd never met, and offered his services. Kahn was intrigued: He'd heard good things about Holbrook's classical acting. Plus, as Kahn puts it, "though I had done 'Merchant' a long, long time ago, my feeling was, 'Well, it's been long enough for me to have some new ideas about it.' "

One idea was to use a modern setting. Holbrook immediately objected. "I felt that this play can teach a more powerful lesson to us all about intolerance and injustice if emotions are wide open and not restrained," the actor says. The play had to be done, he felt, in its original Renaissance era, when despising Jews, not to mention cutting a pound of flesh from someone, was considered part of civilized society. Kahn agreed.

"The whole idea of injustice has always been a big, uh, emotional burr in my life," Holbrook says. His resonant baritone goes flat. Suddenly he doesn't seem quite comfortable.

It's 1927, Cleveland, and the 2-year-old Harold Holbrook learns his mother has left the family. "We never knew why she left, but I'm sure she had her reasons," he says matter-of-factly. "She was a very poor, very young girl." A few days later his father disappears on a search for her. Neither will ever return.

Young Holbrook goes to New England to live with relatives, who find it perfectly acceptable to refer to Jews and other minorities by vulgar names. "It embarrassed me," he says.

When he was not being embarrassed, he was being beaten while attending an elite boys school. "I was sent away to make a man of me," he says, disgust and anger evident in his voice. The headmaster was "a little weirdo. We'd line up--they just called your name out, and you went and lined up outside his office. One by one you'd go in, be told to take your pants down--both of them--grab the arms of an armchair and lean over. Then he took a packing crate slat out of the closet and beat you until you cried."

That was the standard treatment. Holbrook, for some reason he's never figured out ("there must have been something in my face"), drew special attention. "At various times he slapped me, knocked me against the wall, kicked me in the groin. I've never forgotten it." Relief finally came when the headmaster, faced with mandatory retirement, took a gun and blew his brains out. His suicide note, Holbrook remembers, said, "I can no longer live without boys."

The worst part, Holbrook says, was never having been told why he was being beaten. "You never knew what you did wrong. And you never knew when it was coming." He pauses, then spits the word: "sadist."

Emotional burr? Injustice--in particular, the abuse of power--is more like a minor obsession with Holbrook. When the Arab stared at him on that desert road, the actor also flashed on the West's tradition of trying to "civilize" others through imposing Christian values, and he thought to himself, "What idiots we are to think that."

He sees Shylock as a man to whom similar injustice has been done. "When you read about the treatment of the Jews in the 14th, 15th and 16th centuries, and the papal bull of 1555, it's just unbelievable," he says, his voice now rising to the pitch of thunder. Add the pain of his own boyhood to his research, and you have an idea of the Shylock that Holbrook is portraying.

"The thing I love about Shylock is he stood up for what he believed in. This is a man whose fury against the injustice practiced upon him goes to the point of no restraint. When he starts to take that knife, he knows he has broken the law of his religion, because it's against the Jewish religion to shed blood like that. He is sinning, and he will never be forgiven. Because in the Jewish religion there is no forgiveness! So this sweet little speech about 'the quality of mercy' is pure hypocrisy as far as he's concerned! There is no mercy! There is only retribution."

Implacably so.

CAPTION: Holbrook, here as Shylock, is best known for his portrayal of Mark Twain.

CAPTION: Injustice has been an "emotional burr in my life," says Holbrook, whose parents abandoned the family when he was 2.

CAPTION: "This play can teach a more powerful lesson to us all about intolerance and injustice if emotions are wide open and not restrained," says Hal Holbrook of "The Merchant of Venice," now at the Shakespeare Theatre.