In Domesticated, Mary Beth Peil plays four parts: a Shrink, a Mother, a Rich Woman, and a Doctor. But it was another role on her resume that I wanted immediately to ask her about as we settled into LCT's backstage vending-machine canteen before curtain the other night: Anna in The King and I. She was the last person to portray the Englishwoman opposite Yul Brynner, who etcetera'd his way through the Rodgers & Hammerstein musical from its Broadway premiere, in 1951, through the movie version, in 1956, and in subsequent productions until virtually the time of his death, in 1985. 

"I had sung opera for 20 years," said Peil, who trained at Northwestern - a school that also figures in the life of the Domesticated director, Anna B. Shapiro, and the Domesticated playwright, Bruce Norris. "Then I did a Kiss Me Kate at Minnesota Opera, and it turned out to be the perfect crossover part. A light bulb went off in my head and I decided I wanted to pursue more musical theater." 

Cut to: 1983. Peil auditions in New York for Anna for a revival of "King." "First I auditioned for the casting director," she said, "then for the producer and director. They immediately put me on a plane out to Los Angeles, to audition for Yul. Within a 24-hour period I had performed for all of them. I got the part." 

After a month of previews, the revival opened in early October of 1983 in Los Angeles. Around this time, the Rodgers & Hammerstein Organization gave a party to celebrate Brynner's 4,000th performance of the title role. "Just after this," Peil said, "I went to his dressing room to congratulate him, and to tell him that I was feeling comfortable as Anna and that I was ready to really own the part. He said, 'That's fine, but I have to tell you something. I went to the doctor this morning and I was told I have terminal lung cancer. I can't do more than another two weeks of the show.'" 

Except for medical professionals, only three people - Brynner's dresser; his wife, Kathyyam Lee; and Peil -- were privy to Brynner's diagnosis at this point. "We set up little stations around the stage," Peil said. "With water, tissues, and cough drops, in case he needed them during a performance. He had cancer treatment almost every day. He never missed a performance." 

After a post-L.A. hiatus, the production went on tour throughout the United States. It opened in New York on January 7, 1985, at the Broadway Theater. "Sometimes," Peil said, "Yul would have to be carried from his dressing room to the wings. But he never let his illness show on stage, even later in the run when he was occasionally a little weak during the 'Shall We Dance?' number." Peil added: "I learned so much from him." 

Peil has gone on to do roles on television, as well as in both musical and non-musical theater, including LCT's Women on the Verge of a Nervous Breakdown and a recent revival of Sondheim and Goldman's Follies. But when I asked her to choose her most challenging role in the theater, she selected a production of the one-person play M. Proust, done in 2006 at Steppenwolf in Chicago. 

"It was written by Mary Zimmerman," said Peil, sounding again the Northwestern connection: Zimmerman studied there and is currently on the school's faculty, as well as being a close longtime friend of Bruce Norris. "Mary's schedule didn't allow her to direct M. Proust," said Peil, "so it was staged by Eric Rosen." 

Peil primarily played Celeste Albaret, Proust's housekeeper, who late in life broke a half-century-long silence about the writer and published a memoir about her time with him. "The play required such total concentration on my part," said Peil. "I lived like a monk - I lived and breathed that world for weeks." Peil said that Zimmerman has talked about working on the play's script again. If there is a further production, Peil would like another stab at it. "Celeste didn't break her silence until she was in her 80s, so this is that rare case: the older I get the closer I am to the age of a character I've already played." 

At the moment, however, Peil is happy to be a part of Domesticated. "I think I can speak for all the cast," she remarked, "in saying that we are to a person enthralled by the play and the production." 

Peil describes all four of her characters as facilitators. "They drive the story forward and act upon the protagonists played by Laurie [Metcalf] and Jeff [Goldblum]." She added: "I've never played characters like this, who don't have a clearly defined beginning, middle, and end. I have to be very efficient at conveying what each of them says and does." 

Asked about playing the mother of Goldblum's character, who is a public figure caught in a scandal, Peil replied: "There's an obvious connection to the character I play on "'The Good Wife'" - the superb Sunday-night TV series in which Peil plays the mother of the scandal-laden figure acted by Chris Noth. "It's a great gig," Peil says, amused, "though I don't want to start getting typecast as the mother of all the bad boys." 

Brendan Lemon is the American theater critic for the Financial Times and the editor of lemonwade.com