Night @ The Improv

Emily Blunt, Rachel Weisz and Mark Duplass have all joined the cast of an upcoming untitled comedy reports Variety.

Blunt and Weisz will play sisters in the project which will use a lot of improvised dialogue.

"Humpday" filmmaker Lynn Shelton wrote the basic script outline but plot details are unknown.

Steven Schardt will produce the pic

Filming kicks off shortly in Seattle.