Antonio Ferme editor Oscar Isaac and Rachel Brosnahan lit up the stage on Thursday night during the opening of “The Sign in Sidney Brustein’s Window” at the Brooklyn Academy of Music. Set in the 1960s bohemia of Greenwich Village, the play follows a couple struggling to find their authentic selves during a period of radical social change. Isaac said he was drawn to the story’s examination of identities and how they can fluctuate throughout the course of a marriage or a career. “The real secret is there is no authentic self,” Isaac told Variety before the show. “It’s really hard to get to that place because you have to basically die. The ego death has to happen. And then you have to just allow yourself to feel.”