Neal: We know they do run into none other than Henry's dad, Neal (Michael Raymond-James), while in NYC. And he'll be sticking around. Is that because Neal is Baelfire? It's a common theory, though we can't tell you if it's right or not.
A Rumple flashback. The official synopsis explains that the flashback involves Rumple realizing "his destiny while fighting in the Ogres War," and this spoiler also hints that the flashback will involve Rumple's reunion with Bae being foretold.