On the heels of good reviews for her work in The Devil Wears Prada, Emily Blunt has joined the cast of A Walk in the Park, the directorial debut of Tony and Pulitzer-winning playwright (Proof) David Auburn. The film stars Susan Sarandon (who played opposite Blunt in the straight-to-video release Irresistible) as Julia Sandburg, a woman who, on the heels of the disappearance of her three-year-old daughter fifteen years before, "has cut herself off from anyone once near and dear to her." When she stumbles upon a troubled girl named Louise (Blunt) -- in a park, one assumes -- emotions pour out all over the place, and Sandburg is unable to shake the absurd hope that Louise might be her long-lost daughter. Also featured in the screenplay are Sandburg's estranged ex-husband and son, but those roles have not yet been cast.

A Walk in the Park is scheduled to begin film this fall in New York.