Which film did Eileen Heckart star in three years before The Bad Seed?
The Bad Seed (1956 film): The Bad Seed is a 1956 American psychological horror-thriller film with elements of melodrama and film noir, directed by Mervyn LeRoy and starring Nancy Kelly, Patty McCormack, Henry Jones, and Eileen Heckart. Eileen Heckart:  She first became known for her role as schoolteacher Rosemary Sydney in the original 1953 cast of William Inge's play "Picnic" on Broadway.
"Picnic"