Ep 16. Heart of Darkness

Emma Swan, Mary Margaret Blanchard, and David Nolan struggle to find a way to prove that Kathryn Nolan's mysterious disappearance in Storybrooke was orchestrated by none other than Regina Mills. The search for evidence against Regina leads Emma and Mary Margaret to seek assistance from Mr. Gold -- who takes them back to a time long before Regina's rule and into the world of the Brothers Grimm's "Snow White" to hunt for a powerful weapon. Meanwhile, in the Fairytale Land that was, Prince Charming is haunted by an inability to remember a past that he has forgotten. He encounters a cloaked figure who tells him that he must sacrifice his own heart in exchange for killing his evil father - who Charming clearly would rather kill with a sword.