Well I was inspired by something in the Once Upon a Time season premiere pre-show where the creators answer various fan letters while teasing stuff for the new season. One letter asked "When was Darth Vader coming to Storybrooke?" and both the creators smiled and one replied, "What makes you think he's not already there?"
So... what if Vader, or at least a post RotJ Anakin, is in Storybrooke dating all the way back to the first Dark Curse? Obviously, like many OUAT version of stories you'd have to play with things at least a little bit to get him there. But also like most OUAT stories, the newer the story the closer it seems to be to the "original" source material. So... let's put at least the full first two trilogies in play relatively unaltered, but the kicker is that Anakin lived. Luke kept his mask on him until he could get medical aid and he did recover, somewhat. He was also something Leia felt had to be kept hidden if Luke wanted him to remain alive (whether she agreed with him or not) so they reported his death, burned his armor, and kept him stashed away. Unfortunately he was causing mounting tensions between his children and realized that his time in the galaxy was coming to an end. Eventually to try to end the conflict brewing between the twins he chooses to wander out past the boundaries of known space never to be heard from again. The only kicker was at some point he came upon a wormhole and was guided to crash land on the world that contained the Enchanted Forest from OUAT.
I figure he arrived somewhere in the later years of Regina's time as the Evil Queen and, for the most part, chose to stay out of the politics of the region living as a simple hermit as he tried his best to repair his ship. Then he gets caught up in the Dark Curse with everyone else and the broken, mostly prosthetic-bodied, Anakin Skywalker is replaced by fully flesh and blood Kenneth "Ken" Walker, owner of Storybrooke Electronics and the man charged with acting as the IT specialist for pretty much the whole town. Things go on as per canon through at least the breaking of the first curse and now you have a fully able bodied Anakin living in town and observing things around him much more keenly, particularly Regina's struggles with Darkness and redemption and Rumple constantly playing people the same way Palpatine once played him.
From there it becomes a story of Anakin's seeing the parallels between himself and Regina and whether he can bring himself to step in and help her find balance the way Luke (and Leia for all her snippiness) once helped him.
There's the bare bones at least. Although from there my mind goes in a dozen different directions as to when and where Anakin makes himself known again. If it's in season two would he reach out to Regina after she had to destroy Daniel? Or when she was falsely accused of Archie's murder? After Cora's death? And if not then, would he reveal himself in season 3 while the town was dealing with Zelena? I can't see Darth Vader taking being harassed by flying monkeys for very long before he decided enough was enough.
Then there comes the questions of how major factions in town would view him? I could see Emma and Henry both geeking out over his being in town if they learned who he really was. Snow and Charming would be afraid of him I imagine. But the bigger questions would be how the Blue Fairy, Rumplestiltskin, and Regina each viewed him? Well, I would see him trying to reach out to council Regina if nothing else so I could see a friendship developing there. And I imagine Rumple and Blue would both see him as a threat for different reasons, but where would things go beyond that? How would the Force, particularly in the hands of the rejuvenated Chosen One, stack up against the magic of the various heavy hitters in town? How far could Anakin really be pushed if Blue or Rumple tried to manipulate him in any way? And how would it alter the face of Storybrooke in general?
So... there's some food for thought that I would love some feedback on. Let me know what the almighty hive-mind thinks.