The 49-year-old actress dropped by The Ellen DeGeneres Show, airing Tuesday, and talked about the well-received HBO series, which she produced with co-star Reese Witherspoon. Kidman admitted she was initially underwhelmed by the response from the show.
"It was weird, when it first came out I remember calling and being like, 'Awww, I was hoping it would be a little more successful,'" she shared. "I was like, maybe it's not going to hit the place we really wanted it to hit, and then it just started to snowball. And the great thing was, because it was on HBO, everyone had to wait each week to see the next step."
"Then I was suddenly being recognized in airports and on airplanes, and women were coming up to me on the street and talking about the character and what was going to happen next, and I was getting texts from Keith's friends," she continued. "And they were saying, 'We're staying in Sunday night, we're ordering pizza, we're putting the kids to bed, we can't wait to watch!' And then I thought, 'Wow, this is working.'"
Kidman's critically acclaimed performance as Celeste, who's in an abusive relationship with her husband, Perry (Alexander Skarsgard), obviously hit a nerve with viewers. Kidman said she and Skarsgard completely committed to the scenes, to the point where Kidman was experiencing real physical pain.
"I haven't had a film since Lion that's really kind of penetrated in the psyche of the world for a long time," Kidman said. "I felt a sense of duty that I wanted to give truth to such a complicated story, and I wanted it to be incredibly real for the audience, so I threw myself into it, to the point where I would come home at night with bruises and really sore. And he would grab me, and Alexander did not mean to do this -- and I would never tell him that he was hurting me -- because I wanted him to commit to the scenes. Then when people watch them as an audience, they can feel that somehow this is real, and that was important to me because the storyline is about domestic abuse, and that's a very, very important, serious, relevant subject right now."
Of course, the Oscar-winning actress is also proud that she and Witherspoon were able to get a female-driven show on the air.
"When women choose to combine their power, they can get things done," Kidman noted.
ET spoke to the cast of the miniseries in February at the Los Angeles premiere, where we quizzed the ladies -- including Shailene Woodley, Laura Dern and Zoe Kravitz -- on how well they really know each other.