If Clarence Darrow almost, but not quite, stole last season's Never the Sinner from its two protagonists, Leopold and Loeb, the legendary lawyer will now get a full night in the spotlight. In the tradition of solo shows about Harry Truman and Mark Twain comes Clarence Darrow Tonight!, opening Mar. 7 after starting previews Mar. 3 at NY's Ensemble Studio Theatre.

Veteran actor Laurence Luckinbill wrote and stars in the show, which he's been touring around the country in repertory with another solo he brought to Off-Broadway, Lyndon (about LBJ). Other Luckinbill New York credits include The Boys in the Band, A Fair Country, Chapter Two, The Memory Bank and a Tony-nominated performance in 1977's The Shadow Box.

Darrow -- at least the Darrow of Clarence Darrow Tonight! -- was a champion of free speech, decent working conditions and the wrongness of the death penalty. (He considered his greatest achievement saving 102 different cases from the gallows.) Darrow was also immortalized in Inherit the Wind for his defense of the schoolteacher who wished to teach Darwin's Theory of Evolution. According to production spokesperson Jim Baldassare, Luckinbill based his monodrama on Darrow's own autobiography, "The Story of My Life."

Asked about the challenge of bringing to life historical figures such as LBJ and Darrow, Luckinbill told Playbill On-Line (Feb. 24), "With Lyndon, everybody thought they knew what Lyndon Johnson looked like. They had an indelible image. I spent hours and hours at the museum of Broadcasting and tapes from the LBJ library. I worked really hard on that and never felt I achieved it. And even Lady Bird and the daughters commended me on the performance, so I gradually got to feel I accomplished something there...

"For me, since I wrote Darrow, the issue was who really IS Darrow? It's not just the Scopes Trial and the Leopold & Loeb trial, where he stood against the orthodox ideas of the day. He has grown and grown in my estimation. He didn't take the cheap or easy road. He liked money as well as the next guy, but he was not a wealthy man. He was the most esteemed lawyer of his time, but he was so honest. Did you know he got stiffed by his clients in the Leopold & Loeb thing? They begged him to take the case, he took it -- even though he had a deathly flu -- and then, when he saved their lives, they refused to pay his fee. He ended up going to arbitration and got only a fraction of what they agreed upon." Continued Luckinbill, "I tried really hard to capture a moment in his life, when he became Clarence Darrow, with big C and big D. Before that, he was just another corporate lawyer. But the 1894 Railway Strike was a life changing decision: will you continue to work on the side of the strong (and big, big money), or work for zero on the side of the weak. He didn't want to leave his employment -- by his early thirties, he was earning more money than the President of the United States -- but he was uncomfortable working for the Railroad. He became a labor advocate -- a dangerous and, at times, dirty and violent business. In fact, toward the middle of Darrow's life, he got in trouble philosophically with what he believed. That's what the play is most about. It's about the man in full."

Luckinbill came up with the shape of the piece when he saw the only known extant footage of Darrow -- as an old man on a "March of Time" interview. "The play starts with Darrow as an old man," Luckinbill said. "He's been invited to lecture but comes not quite knowing what the subject is. Turns out, the subject is: What is Justice? He sincerely and emotionally tries to find the answer."

Notes Luckinbill, "Inherit the Wind wasn't Darrow at all; it was completely rewritten. His Leopold & Loeb summation is American Shakespeare. It took twelve hours. And at the end of it, one reporter said that when Darrow approached the bench, his voice was indistinguishable from the silence in the room; he had so spent himself. He gave everything he could in defense of indefensible people. They called him `the attorney of the damned.'"

The man, as much as the trials, will be central to Clarence Darrow, Tonight!. "The issues are complicated and have to be explained in dramatic terms. I'm pretty sure I've succeeded, but a one-man show is very lonely. As a performer, you hyperventilate, you have no spit left. As Phyllis Newman said when doing The Madwoman of Central Park, the worst thing is when the stage manager knocks and says `Places, please." My wife [Lucie Arnaz] even says, `I couldn't do what you do. I like people too much.' She likes musicals where you can talk and sing and go out with people afterwards. My cast parties are lonesome affairs. Still, I'm convinced I've found my niche; not just one-person shows. But historically important American characters who dealt with issues in a gutsy way." [He's already working on his next, Nuremberg Revisited, which deals with a man who had access to the Nazi criminals on trial.]

For tickets ($12) and information on Clarence Darrow Tonight!, which runs through March 21 at E.S.T., 549 West 52nd St., call (212) 247- 4982.

-- By David Lefkowitz