Once Upon A Time 4x16 "Best Laid Plans"
Mary Margaret: I can't do this. I gave Henry that book to give him hope, and I'm gonna lie and take it away? And what about Regina? She's finally becoming a friend. I went to her for help with Emma, with our secret. She's kept it. She's risked her life for us. And we're gonna repay her by destroying her chance at a happy ending?
David: Well, maybe there's another way.
Mary Margaret: No, David! When Regina showed me my heart after Cora... after I killed Cora... My heart was dark. And Regina thought it was because of what I did to her mother. But that darkness started long ago. We... have to tell Emma the truth. Because heroes do what's right, not what's easy.
