Stern and Adam Del Deo will co-direct and produce and WMi is handling worldwide rights here on A Chorus Line's famously tumultuous career.
The film-makers will cull behind-the-scenes footage of rehearsals and performances from the 1975 original and the 2005 revival.
'The story behind this new production and the 1975 original is as compelling as the show itself,' Stern, who has produced 15 Broadway and off-Broadway shows including The Producers, Hairspray and Stomp, said.
'We look forward to bringing Every Little Step to the Cannes Film Market and know that it will resonate with buyers, and subsequently audiences, worldwide.'
Stern and Del Deo previously collaborated on the documentaries So Goes The Nation and The Year Of The Yao.
Endgame is currently shooting The Brothers Bloom starring Rachel Weisz, Adrien Brody, Mark Ruffalo and Rinko Kikuchi, and is in pre-production on the teen thriller Solstice. Its credits include Todd Haynes' Bob Dylan title I'm Not There with Cate Blanchett, Christian Bale and Heath Ledger.