It is perhaps fitting they're sharing the same Camelot these next few weeks since, as she duly footnotes at the outset of her show, they come from the same place, too. Half a century ago, they were among the Theatre World picks for Promising Personalities of 1954-55—he for The Dark Is Light Enough, she for Plain and Fancy—and it's a promise they've fulfilled time and again. Now they're deep into their valedictory days at the Beaumont. Cook rules the roost Friday, Saturday and Sunday nights while Plummer rests and regroups for his next massive stage charge the other four nights—a kind of theatrical lend-lease that lapses April 18 when Lear ends and its Canadian cast retreats north.

Plummer lingered after his Lear matinee to catch Cook's act and visit her backstage before motoring back to his Connecticut home. Other first nighters included Dixie Carter, who had just that day gone into Thoroughly Modern Millie; George Grizzard, whose Cat on a Hot Tin Roof in D.C. is still currently missing a Brick ("Austin Pendleton volunteered."), Harvey Evans; and a full complement of Lincoln Center playwrights (Wendy Wasserstein, John Guare, A.R. Gurney, Alfred Uhry).

Barbara Cook's Broadway cuts a lovely swathe of Show Tune Concentrate through the golden era of musical theatre. Cook, of course, was part of that gold—only, she says, she didn't realize it at the time. "Do you suppose"—frightening thought—"we're in a golden era now?" she asks. The program runs 95 minutes, from Camelot's "I Wonder What the King Is Doing Tonight?" to Candide's "Glitter and Be Gay" (which Bernstein composed on her voice) and Bells Are Ringing's inevitable curtain wringer, "The Party's Over." And whaddayaknow? It was a party.

What in a lesser mortal's hands would have been a cabaret evening was, as Cook cooked it, a master class in musical theatre acting. And that may account for the fact that so many cabaret headliners were in attendance on opening night and at the party afterward in the Kaplan Penthouse. Maria Friedman, who's having her second coming at the Cafe Carlyle Tuesday, spent much the evening singing Cook praises to another Carlyle chanteuse, Ute Lemper and said she's sprucing up her new act with a couple of songs from the show she'll do next in London, Andrew Lloyd Webber's The Woman in White.

"I love her openness," said Ann Hampton Callaway, who's currently sharing Feinstein's at the Regency with sis Liz. "She is so who she is. Barbara has such an unabashed enthusiasm for the characters that she's playing and for the emotions that she's playing. Once she receives the applause from the audience, it's such a beautiful relationship." Donna McKechnie, London-bound in two weeks to break in a new act she's calling Gypsy in My Soul, was trying to figure out why this was her favorite night of Cook-ed songs. "It was something subliminal," she offered. "Her soul came through in a way. The numbers were completely from the golden age. I guess I'm really hungry for that time."

Lyricist Sheldon Harnick was rhapsodizing as well. "Barbara is such an artist, and, as somebody commented tonight—I think it was Jerry Bock—she has never been more transparent. Everything she was thinking, everything she was feeling, just communicated so directly to the audience. And the voice is still lustrous as ever, maybe even more so."

True, Cook did give the Harnick-Bock songbook a good workout—"four from She Loves Me, one from Fiorello!," by Harnick count, and not necessarily songs she introduced. "It was almost as though she was singing them for people who played the original roles and saying, `This is the way you should have done it.' It was an extraordinary experience."

Cook has been working without a net—a character to hide behind—for a tad more than 30 years. "February was our anniversary," she said. That's when she began her glorious second act as a cabaret performer at the Brothers and Sisters on West 46th Street, and the fourth wall separating her and her audience came resolutely tumbling down, never to rise again (save for a brief aborted wrestle with the monster mom of Carrie in Stratford upon Avon in England, of all places). Cook has been on a one-to-one basis with the audience ever since.

"I wish I had words of wisdom about that, but I don't," admitted the man who made this leap with her, Wally Harper, her accompanist, arranger, musical director and friend. "The chemistry was there the first time we worked together. We think alike musically. We have the same musical shorthand. It just fell together. I have no explanation for it."

It may well turn out that—after Ado Annie, Carrie Pipperidge, Hilda Miller, Cunegonde, Marian the Librarian, Liesl, Julie Jordan, Magnolia Hawks, Amalia Balash and Dolly Talbo—Barbara Cook's greatest role will have been Barbara Cook. Her Broadway runs six more performances at the Beaumont. Long live the Queen!

—Harry Haun is staff writer for Playbill magazine, and has been attending Broadway opening nights since 1975.