The previously reported pic is inspired by the 1975 documentary of the same name (by Albert and David Maysles), which also inspired the recent Tony Award-nominated Broadway musical.
A Maysles followup doc, "The Beales of Grey Gardens," was recently released, to be followed by a third Al Maysles documentary about the musical ("Grey Gardens: From East Hampton to Broadway," produced by the Broadway show's producers).
In the feature, Lange will play "Big Edie" Beale and Barrymore will play her daughter, Little Edie, with shifts between the characters' heyday and their age of decline. The Beales made headlines in the 1970s for living in a squalid East Hampton mansion called Grey Gardens.
This is the first report of HBO Films being involved in this non-musical film project.
The trade paper noted that Michael Sucsy is directing and wrote the script with Patricia Rozema ("This Might Be Good"). Executive producers are Rachael Horovitz ("Little Black Book") and Lucy Barzun Donnelly ("The Go-Getter"). David Coatsworth (HBO's "John Adams") is producing.
There are two cast albums of the musical on shelves: One for the Off-Broadway run of early 2006 and one of the 2006-07 Broadway cast (with score revisions).