Three years ago, Edie Falco originated the role of Side Man's Terry in a staged reading at the West Bank Cafe. Though the Warren Leight play was still in its very early stages, Falco felt an immediate connection with the emotional, loquacious mother. "Terry's not well-behaved, and I kind of loved that," Falco recalls. "There is something very cathartic about playing someone who could care less about how she is perceived. I was excited about the prospect of playing her."

At the time, she was a struggling actress who supplemented her earnings by waiting tables. But success arrived quickly for both Side Man and Falco. The play was produced at Vassar College's Powerhouse Theater, and then at the CSC Theater, where it drew raves from critics -- and a Theater World Award for the actress, who soon found herself divided between Side Man, a regular role as prison guard Diane on the acclaimed HBO series "Oz," and a starring part on a pilot called "The Sopranos. "

As Side Man's CSC run drew to a close last spring, rumors circulated that it would either be extended or picked up by a Broadway theater. At the same time, HBO began expressing interest in "The Sopranos." For Falco -- who knew her schedule could not accommodate "The Sopranos," "Oz," Side Man and her many film roles -- it was a heady and nerve-wracking time. "Everyone was very excited that Side Man had done so well, and that they were thinking of extending it," she remembers, "and in the back of my mind was, 'If "The Sopranos" is picked up, I'm in deep trouble.' And indeed it was."

Because of her intense "Sopranos" shooting schedule, Falco had to jump ship at Side Man just before its Roundabout Theatre incarnation at Criterion Center Stage Right. "The worst part was, I wanted more than anything to be thrilled that [Side Man] was moving," she says. "But at the same time, the thought of it moving without me just blew my mind." The actress admits she felt "very terrible" about leaving the show -- which also meant forfeiting her Broadway debut. "You try to remember that these are just jobs, but somehow this one got in deeper than other jobs," she relates. "I took it kind of hard."

Falco was replaced by Wendy Makkena, and fulfilled her 13 episodes as Mafia wife Carmela Soprano on the HBO series. When she finished shooting in November, Side Man was still up and running -- and about to move to the Golden Theater. "Never in a million years did I think that the play would still be going on," she relates. "It actually got a little sticky there, because I could have opened the play at the Golden, but it was Wendy's role at that point. I no longer had any hold, contractually, on the part. Like a two-year-old, I was stamping my feet, going, 'This is my play.' It was horrifying." But fate intervened. "As it turned out, Wendy got pregnant, which sort of worked in my favor," the actress says. "I'm sure it worked in her favor as well." Falco took over as Terry on Jan. 8. The role hadn't changed at all since the CSC run. Neither had the cast -- with the exception of Christian Slater, who'd signed on as Terry's son Clifford.

Still, Falco hadn't played the part in nine months. And appearing on a Broadway stage for the first time in her life -- with little-to-no rehearsal -- was frightening at first. "It was a bit like the dream that all the actors have at some point," she says. "I've had plenty of those dreams myself -- I dreamt one time that I was taking over the role of Lady Macbeth from Cher. But this was the closest I've ever been to actually being in that dream."

The dream has turned out to be a pleasant one. Broadway audiences have been enthusiastic, her castmates have been supportive and, Falco says, she loves Terry as much as ever: "What could be more exciting than being out there with this play -- and this character whom I know -- and just rolling with it?" Her schedule remains extremely busy. Recently, the actress took a week off from both Side Man and "Oz" to attend the Sundance Festival, where her friend Eric Mendelsohn's new film "Judy Berlin" (Falco plays the title role) garnered an award.

When Slater leaves Side Man at the end of February, he'll be replaced by Robert Sella, who played Clifford at CSC. ''Exactly one year ago on Mar. 3, we opened at CSC together," Falco points out. "Now, we'll all be performing on Broadway together."

Falco hopes the reunion lasts a long time. "I'd like to do Side Man as long as I am physically capable of it," she says, smiling.