So, what really happens at the end of the movie?

Mary’s friend, Elaine (Shanola Hampton), ends up stabbed to death, but it’s not totally clear who killed her. On the surface, it appears that it might have been Grace, who suddenly exposes her more sinister side, known as Margaret, when she goes after Mary and Tom.

But is that really what happened? Or, was this all in Mary’s head? Did she actually kill Elaine to live out her book, given the police evidence? Or was the movie itself meta, as in, we were just watching the plot of her book?

We may never know what was an illusion and what was reality, because Greer, 29, has one simple explanation: “To me, it’s like, you’re supposed to draw your own conclusions. You’re supposed to come up with your own theories. There isn’t supposed to be an answer to that. That is all on you, as a viewer, and what you want it to be.”