The spinoff is called The Expendabelles, and will begin production at the beginning of 2015. Robert Luketic (Legally Blonde) is attached to direct, with Avi Lerner as producer. Lerner produced all three Expendables films, and told reporters at The Expendables 3 premiere in London he has several actresses in mind for the female ensemble cast.
Stallone said he personally would love to see Alien franchise star Sigourney Weaver portray his character Barney's wife in order to tie Expendables and Expendabelles together.
"Are the Expendabelles really part of a divorce where Sigourney Weaver, who's my wife, inherited half of the Expendables?" he posited. "She'd get the house, the kids and my mercenaries."
The Expendabelles will reportedly follow a group of female mercenaries on a hostage rescue mission, who must also topple an evil dictator once they are behind enemy lines.
"With Expendabelles you've got a situation where we're in uncharted waters to put all women together and think, 'Will that really work?'" Stallone said of the spinoff. "We don't just want to use the name -- it needs to be something that can hold its own."