Rachel Weisz and Emily Blunt are set to mumble together on a new movie.

The latest from mumblecore director Lynn Shelton doesn't have a title or plot yet, but we know that the actresses will be playing sisters. Since Cyrus took the movement mainstream with its big-name cast of John C Reilly and Jonah Hill, Shelton's duo are set to eclipse that line-up. 

Shooting starts in a couple of weeks and will only last a couple of weeks. Which is why Weisz can fit it into her schedule between Terrence Malick's new film and a part in The Deep Blue Sea. It should be interesting to see the two talented actresses taking on the challenge of improvising dialogue for 90 minutes. And no, The Devil Wears Prada doesn't count.