Directed by Julie Taymor (Across the Universe), the movie is due to debut on Amazon Prime on September 30 and is being talked about as an awards season contender.
Moore and Vikander previously worked together on a very different film, the 2014 fantasy epic Seventh Son. And in a show of female solidarity that makes her casting as Steinem feel even more perfect, Moore stepped in when Vikander was subjected to a sexist and distasteful comment from a man on set.
Vikander, who was just 20 at the time and very much starting out in the industry, told Elle: "I was just thankful to be there. I was afraid of speaking up or losing respect, or that people would find me difficult."
Recalling how Moore spoke up powerfully on her behalf, Vikander continued: "I think she was like, 'If you ever say anything like that again, I’m leaving and we’re done.' That changed my situation on set going forward and it meant the world to me."
During the interview, Vikander also said that though she has never experienced sexual harassment on a film set, there have been times when the workplace atmosphere felt overly sexualised – something which many of us will relate to.
"It’s mostly been men, but women too, who have talked about sex on set in a way that I just don’t find appropriate in a workspace at all," she said. "I understand what can go wrong in those situations."