It belonged to her father, Chicago actor Bernard Beck. His daughter soon realized that she was writing it for him.

Now the play, "Number of People," is having its world premiere at Evanston's Piven Theatre Workshop, with Bernard Beck in the role of the single character, Leo Gold, an aging statistician and Holocaust survivor.

In a three-way call that could have doubled as a mutual admiration society, both Becks talked abut the work and its genesis.

It all began, Emilie Beck says, in 2003, after she had just given birth to her first child. "I was feeling very stuck at home with a crying, colicky baby and I thought, I'll never do anything ever again in my life," says the younger Beck, a Los Angeles playwright and director who returned to Piven, her original theatrical home, in 2008 to helm the award-winning play "Because They Have No Words."

Soon, though, she began thinking about the wars in Iraq and Afghanistan and the genocide in Darfur. "I was altogether feeling very much like there were things happening in the world that I felt angry about, and I wanted to have a voice," she says. She began researching genocide and related topics.

Then, she says, "I started thinking about our collective memory, why we always repeat history. I started realizing that the Holocaust survivors still alive at this point may be starting to lose their memories or to have their memories come back to them. I fused all of those things together and created a character who is losing his memory and dealing with having to reconcile that with everything that went before. The more research I did, a voice that fits (the character's) voice really spoke the play for me."

It wasn't surprising that that voice was her father's. Bernard Beck, who is also an associate professor emeritus of sociology at Northwestern University, has been appearing in Piven productions for 30 years after beginning his acting career in Paul Sills' legendary Story Theater. He is especially notable for works at National Jewish Theatre and Chicago Jewish Theatre, and he is known to generations of Chicago Jewish children as Hershel in the Yiddish Theatre Ensemble's production of "Hershel and the Hanukkah Goblins."

Of his daughter, Beck says, "Can you guess how proud I am that she turned out so magnificently?" When he read the play, he says, "I was impressed with how well she had captured the issues. It was very moving, and I felt immediately I would like to play it. As I read it, I heard my own voice saying the lines-I knew how easily I would rise to those tones, inflections, jokes. At some point, she did tell me she had written it for me."

There's a kind of story-within-the-story theme at work here too: The play involves a father-daughter relationship in which the daughter, an artist, paints scenes that connect to her father's childhood even though she had no direct knowledge of it.

Something similar is true in his own family as well, Bernard Beck says.

"No one in our immediate family was a victim of the Holocaust-every Jewish family has some relatives who were, but nobody (Emilie) or even I grew up with. How does she know about this? When I think about it, it's a tremendous mystery, and she is touching points in my own dealing with it. How do you know such things? There are things we know that we can't say how we know them. They aren't in a book. The feeling, the sense of what people went through, what they felt-that's why artists are artists, they have a sense of being able to communicate these intangibles," he says. He calls the play "a mix of the facts and feelings."

He adds that in addition to being an artist, Emilie is a gutteh neshama-a good soul. "She is sensitive, she empathizes in a way that I am very proud of. I think I must deserve a little bit of credit," he says.

"I think you get a lot of the credit," she responds.

When the play was finished, Emilie Beck went the usual route of readings and workshop productions, working at the Pasadena Playhouse in California with director Shira Piven, the daughter of Piven Theatre founders Joyce and Bryne Piven. Because of other commitments, Beck was not able to appear it. "I had to get a stand-in," Emilie Beck jokes-Ed Asner.

Both Becks immediately thought of the famous actor in the role; Shira Piven sent him the script and he agreed to appear, and did so in several staged readings and benefits in and around Los Angeles. (The current production marks the first time the play has been fully staged.)

"He was wonderful. I have always thought of him and Bernie as being very similar, but he gave a whole different read to it, and that was very interesting to me as a playwright," Emilie Beck says.

Bernard Beck's caught several of Asner's performances and says, "I learned a lot from him. He's fabulous, monumental. I kept saying, I prefer my own way, but now I'm coming closer and closer to his way. My approach has been approaching his approach."

Meanwhile, as the Piven production comes together, "people always say, isn't it a problem, a father and daughter working together?" Bernard Beck says. His answer: "Absolutely not. I have complete faith and trust in Emilie. We have had a lifelong conversation about theater that hasn't always been sweetness and light but always worked smoothly."

"We really talk things through, which is great," she says. "Bernie has been in theater practically my whole life and I have hung around theaters from childhood in his orbit. When I went to college in the theater program, it was like, I know all this already."

"There is so much to this play," her father says. "In all modesty, I think people will find it a really rewarding experience."

"I can't top that," Emilie says. "I think Bernie is going to give a wonderful, moving performance."

"Number of People" opens Monday, March 8 and continues through Sunday, April 11 at Piven Theatre Workshop, 927 Noyes St., Evanston. $15 previews, $25 regular performances. For show times and tickets, call (847) 866-8049 or visit www.piventheatre.org.