Author's Notes: I've been working on this fic since April. It's been a real labor of love and now I'm finally ready to start sharing it with you all. All the thanks in the world to The Mafia, as always.

This is set right after 1x17 Hat Trick and goes AU from there.

Title, as well as lyric snippets throughout the fic, taken from the song The Road You Didn't Take from the musical Follies.

The worlds you never see
Still will be around,
Won't they?

"A real world. How arrogant are you to think yours is the only one? There are infinite more. You have to open your mind. They touch each other. Pressing up in a long line of lands, each just as real as the last. They each have their own rules. Some have magic, some don't, and some need magic."

"What is that?"

Emma's head shot up at the tone of Regina's voice. The mayor had been in her office, droning on angrily for nearly half an hour and Emma had tuned her out after the first five minutes. Regina was enraged – to say the least – that Mary Margaret had been in her holding cell ready for the arraignment and so she'd been taking her anger out on Emma. As if that was anything new or different.

What was new and different though, was the hitch in Regina's voice when she had asked her most recent question.

Emma followed her gaze to the hat that she had made at Jefferson's, the one that had fallen out the window with him. She'd picked it up and brought it back to the station with her for reasons she couldn't quite put her finger on. She'd dropped it on the top of a shelf and promptly forgotten about it when Regina had entered in a rage. But now Regina's gaze was focused on the hat like a laser beam.

Emma frowned and replied as though she was talking to a two year old. "It's a hat, Regina. People often wear them on their heads."

"I am well aware of what it is, Miss Swan!" Regina snapped back. "What is it doing here? Where did you get it? Why do you have it?" With each question Regina moved closer to the shelf until Emma herself stood up and picked up the hat.

"It's a hat, Regina." She repeated. "Why do you care where I got it or why I have it?"

"Answer the question." Regina demanded.

Emma felt a headache coming on. She was tired and sore and in no mood for Regina's little tantrums. Plus, there was no way she was going to tell Regina where she'd gotten the hat, because if she did, then the mayor could use the information to figure out that Mary Margaret had tried to run away.

"I made it, if you must know." She bit out, moving around Regina towards the door to her office.

"You made it?" Regina sounded skeptical and Emma couldn't really blame her for that. "Why?"

Because a madman was holding a gun to my head! she wanted to shout, but she just rolled her eyes instead. "Thought I needed a new hobby." She snarked, opening the office door.

"Do not walk away from me, Miss Swan. We are not done here." Regina's voice was low and threatening.

Emma spun around and stared at her. "I don't have time for your games, Regina. I have a job to do. It's a freaking hat. Take it for all I care!"

And with an angry flick of her wrist, Emma sent the hat spinning across the room before she turned and walked out of the office.

But the hat didn't fall to the ground in front of Regina as Emma had assumed it would. Instead, it began to spin faster and faster, and Regina's eyes widened as she realized – too late – what was happening.

She tried to move backwards, to get away from the hat, but she couldn't. The vortex that had been created was already too strong and she couldn't move away from it. Instead, she was sucked into it, the world swirling and spinning around her before it all went black.

You take one road,
You try one door,
There isn't time for any more

Regina opened her eyes, sucking in a shocked breath when she took in the hall of doors that she'd only been in once before. Although she knew when she'd fallen into the hat that this was where she'd end up, it still shocked her because it shouldn't have been possible. And the repercussions of what it meant that she was there now were reverberating wildly in Regina's brain.

If Emma had made the hat as she said, then that meant that the woman possessed magic far greater than Regina ever would've imagined - not that she'd ever imagined that she had any magic at all. This was supposed to be a land without magic, after all. And even if she hadn't made the hat, she still had magic enough to make the hat work when she threw it.

But more than dealing with what being here meant, Regina knew she needed to deal with how to get back to Storybrooke. The hat had rules - rules that Jefferson had warned her of. Same number out as in was the only one that she'd really cared about at the time of her first entrance into the hat. But now she remembered, vaguely, that in order to get out of the hat, you had to choose a door and enter a world. Only by entering a world could you leave it - and the hat - behind.

Regina's eyes scanned the doors. There were only two that she recognized - the looking glass that would lead to Wonderland and the large green door that would lead to Oz - but neither of them were options for Regina. She would not set foot back in Wonderland, not even for one second. Even thinking about going back there and possibly having to face the woman who lay beyond the glass made her shudder. And since Elphaba's death at the hands of that farm girl, Oz had been practically overrun with those annoying little munchkins and the even more annoying Glinda. No, neither of those doors were options.

She tried to discern where any of the other doors might lead, but none of them looked at all familiar. Jefferson hadn't pointed out any of the others or explained the worlds that they led to or the rules of those worlds. So she would just have to pick one and take her chances. After all, she reasoned to herself, she would only need to spend a few seconds in whichever world she picked. She would enter and exit and be back in Storybrooke in no time, where she could work out how to deal with this new found information about Emma Swan.

Turning, Regina's hand reached out, intent on opening the nearest door. But as she turned, another door caught her eye. It was a deep red, redder even than her apples, and there was some kind of a carving in it. Letting her hand drop, Regina moved closer to the red door, inspecting it. The carving was a large heart, with various lines, curves, and swirls arranged inside of it. Regina tilted her head, trying to make out what the lines could possibly symbolize, but she couldn't make any kind of sense of it.

Still, she felt somehow drawn to this door and so, after running her fingers over the carving one more time, she grasped the knob and pushed open the door. As soon as she had stepped through the doorway, the door closed tightly. And only then, with Regina inside, did the lines, curves, and swirls shift and move, assembling themselves into words within the heart.

The Road You Didn't Take