The two actors, who previously worked together in the 2011 movie "The Help", are reuniting in an upcoming holiday comedy produced by Chastain.
During a panel discussion at the Sundance Film Festival, Spencer recalled how Chastain, 40, negotiated equal pay to hers for "The Shape of Water" actor.
"About 15 months ago, Jessica Chastain contacted me and said, 'I want us to do a comedy,'. Im like, 'Yeah!' She called me six months later, which would have been last March, and we were talking about pay equity with men and women. She was like, 'It's time that women get paid as much as men.' I'm like, 'Yeah Jessica, it's time!' We were dropping F-bombs and getting it all out there.
The actor got emotional as she told her story.
"I love that woman because she's walking the walk and she's actually talking the talk. She said, 'Octavia we're gonna get you paid on this film. You and I are gonna be tied together. We're gonna be favoured nations, and we're gonna make the same thing.' Fast forward to last week, we're making five times what we asked for," she added.