"Emma. Emma! Emma, NO!" Regina bolted upright in bed, the reoccurring nightmare, once again, invading her attempts at sleep. Her shoulders slumped as she took a deep breath to steady her heart. She was alone in the house, glad that Henry had gone with Robin and Roland to the outskirts of the woods surrounding Storybrooke. Henry didn't need to worry anymore about her than he already was his other mother.

Regina's thoughts went to Robin. When had things gotten so complicated? Back when Emma brought Marion back from the Enchanted Forest? When she learned Zelena was really Marion? With the declaration of Zelena's pregnancy? When she decided not to incinerate her? Regina shook her head. This had nothing to do with Zelena. Regina touched her fingers to her lips, recalling the kiss she shared with Robin as she said goodbye to him earlier that day. Her heart hadn't been in it, not like it had the hug she gave Henry before sending him off holding Roland's hand. She loved them, all of them, but at that moment all she could think about was Emma.

Regina tossed her head back and huffed. All she thought about lately was Emma! Her waking moments, her dreams, consumed by the Savior turned Dark Swan. The Dark One. Regina had once told Rumple that she wouldn't allow him to turn Emma dark, but that's inadvertently what happened, though not in the way it was originally intended. His darkness, the Dark One's, that Rumple had tethered all these centuries, consumed Emma and took her away. If she was being honest with herself, it wasn't Rumpelstiltskin's fault at all, it was her own. Emma's choice had nothing to do with Gold's influence and everything to do with Regina's preservation. Regina had made her decision to protect Emma from Gold's darkness, yet Emma had taken that darkness for her.

Regina hung her head and looked down at her intertwined fingers gripping the sheets. Oh, she knew that darkness well. It hung like a shroud all around, waiting to pounce, willing a minute thread of weakness to reach out and touch it, draw her back. Regina knew the lure of evil, the all-consuming lust for revenge, the pleasure in power beyond imagination. She knew, in part, what Emma was going through because of her. And that's the part that hurt the most.

Realizing this line of thinking could prove dangerous, Regina flung back the covers and flipped on the light. The shadows retreated. She shuffled out of her room, flipping lights on as she made her way to another part of the house to pour herself a double whiskey straight up. She debated on sleeping pills, but those only served to cloud her judgement and make her groggy. "Maybe a sleeping curse!" she spat at the air. "Anything right now would be better than this!"

Regina felt guilty, responsible for Emma's sacrifice. "Why didn't you just let me go, Swan? It would have been so much easier being on the dark side again, fighting my way back, with you on this side as my counterbalance, than to be here, alone, without you."

Just then a knock on the door startled Regina, causing her to slosh whiskey over the rim of her glass. Licking the liquid from her finger, Regina made her way to the door.

"Mary Margaret! What are you doing up at this hour?" Regina opened the door wider to allow her to push in the stroller with a sleeping Neal.

"Neal couldn't or wouldn't sleep at the apartment, so I decided to take him for a stroll. When I saw your lights on, I thought you might be having the same trouble," she explained.

Regina snorted. "So, you're going to offer me a ride in the stroller in hopes I'll fall asleep? I don't think I'll fit." She punctuated with a close of the door.

"Perhaps if you drink this…" Mary Margaret offered.

Regina turned around, expecting to find a vial full of shrinking potion from Wonderland. All Mary Margaret held was a small bottle of milk.

Regina wrinkled her nose. "Warm milk? I'll stick to something stronger, thank you." Regina raised her glass in a mock toast before taking a sip.

"Lots of lights on for the middle of the night…." Mary Margaret allowed the unspoken to hang in the air.

"I needed a brighter perspective." Regina grimaced. She was, not now, not ever, afraid of the dark, as Mary Margaret might have been implying. However, there was no sense courting temptation.

"Any luck with the dagger?" Mary Margaret asked as they reached the sitting room.

Regina shook her head, not wishing to divulge yet another lie. She'd thought they were past all the untruths, and was loathe to speak them aloud.

Mary Margaret saw straight through her. "You haven't even tried," she stated as she sat down on the sofa.

Regina tossed up one hand. "I just feel so guilty!" She flopped onto a chair across from Mary Margaret.

"Regina, we've been over this. Emma made her choice." Mary Margaret countered.

Regina shook her head. "Not for that, for deceiving everyone. Hell, we've got David and the Pirate on one side of Storybrooke with a fake dagger, Robin and Henry on the other side on a wild goose chase."

"It's for their protection. We both agreed on that." Mary Margaret reminded her.

"Then why aren't you with them?" Regina retorted.

"Because I'm here for you."

Regina shook her head and knocked back the rest of the whiskey. "What if we were wrong?"

"There's a reason Emma didn't come when we all tried to summon her, not for Killian, nor myself, nor David, even Henry. No one else seems to understand it, but I do. And I think you do too."

"Maybe she just doesn't want to be here." Regina fondled the glass, looking into its depths, as if there were answers there.

Mary Margaret looked at her with knowing eyes. "You're afraid."

Regina gave her a perturbed look.

Mary Margaret ignored her and pressed on. "You're not afraid she won't come. You're afraid she will."

"I am not afraid of the Dark One!" Regina gave Mary Margaret a scathing look.

Mary Margaret leaned forward and put her hand over Regina's. "Regina, I've known you longer than anyone else in Storybrooke. You are the strongest person I know. The only one that can beat the darkness. You've already done it. So, I know you're not afraid of the Dark One or the power she wields. What about Emma? When she comes to you, Regina, and we both know she will, what is it that you fear?" Mary Margaret didn't expect a response. It wasn't a question intended to be answered.

Regina simply stared at Mary Margaret, giving nothing away.

Mary Margaret moved to go. "Even if you don't trust yourself, I do. I trust you with my daughter's heart. Don't delay, Regina. She's waiting. Waiting for the right voice to call her home."

Regina stared after Mary Margaret as she closed the door silently behind her. A well-manicured hand went to her face. Mary Margaret was right about one thing, she was afraid. Not of the Dark One, but of the Dark Swan. The pull of Emma's dark power, raw, uninhibited, easy. Regina knew she was strong enough to stand against the Dark One's bait, but would she be able to stand firm against the darkness in Emma's soul? Regina rose and set the glass on the counter, then she went to the nightstand beside her bed. With a wave of her hand, Regina released the protection spell that surrounded the drawer and pulled it open. The Dark One's real dagger lay inside. Regina took it out and cradled it in her hands.

"Oh, Emma," Regina breathed as she wrapped her fingers around the blade and clutched it to her chest. The guilt, the sense of responsibility weighed on her mind. Her heart ached for Emma, an unmistakable pain that wouldn't let up. There was a void somewhere deep inside her, a part of her soul that was incomplete, missing. She hadn't realized just how empty she still was until Emma disappeared. Emma was gone because of her. Regina's grip intensified.

Hot tears streamed down Regina's cheeks as she remembered the cries of agony torn from Emma's lips as the light was wrung from her. "I would have borne this for you, Swan. It should be my name on this dagger." Without realizing it, Regina grasped the blade with greater intensity. The pain in her heart was so overwhelming, she didn't notice her blood coursing down the edges of the dagger, forming a single drop on the tip. Hanging for an endless moment, it finally let go and splattered at her feet.

"Regina," it was a mere whisper.

Regina looked down. "Regina, Regina, Regina," the whisper echoed over and over from the blood spreading toward her feet.

Regina released the dagger's blade and turned it to get a look at it. Her blood was filling the etching of Emma Swan's name.

"Regina, Regina, Regina." The whisper echoed. "Call for me, call for me, call for me."

"Emma?" Regina spoke to the voice. She looked around the room, but there was nothing to see. Regina could feel her, could feel the Dark One's presence everywhere and yet, in no particular place.

Regina raised the dagger in front of her, "Emma Swan, Dark One, come to me."

And in a cloud of black smoke, Emma appeared. "It's about time. I've been waiting for you," she spoke, her voice held an edge of foreboding. Emma reached out for Regina's hand. She held it palm up, and placed her own over the top. Instantly, the gash was healed. "There, that's better." Emma continued to hold Regina's hand in her own, while her eyes held Regina's. "You mustn't agonize. I will always come if you call me. Now, what is your desire, My Queen?"

Regina stood, transfixed by the vision in front of her. Mary Margaret was right, Emma was here, and she was afraid. Not of the darkness, not of its lure, not of its power, but because it was she and only she who'd been able to summon her.

"I see you've worked it out, Regina." Emma dipped her chin and closed her eyes, only to reopen them and look up at Regina under her hooded lids. It was almost seductive. Emma walked, making a circle around Regina, brushing an arm against Regina's back as she did so. "You are the only one who can handle this, can handle me." Emma, once again, stood in front of Regina.

"But I heard you tell Hook you loved him, just before you changed." Regina relaxed her arm and dropped the dagger to her side.

Emma smiled and tossed her head back slightly. "The truth was spoken, but he doesn't have your strength, Regina, your mettle, your desires. Killian is a part of Emma's life, just as David, Mary Margaret, and Henry are. But you, you own a stronger part of me, a deeper part of me." Emma narrowed her eyes at Regina. "I know my mother trusts you with my heart, Regina. Do you trust me with yours?"

Emma reached out her hand and placed it over Regina's heart. A jolt of adrenaline slammed into every nerve ending, every pleasure seeking part of her aroused with an intensity she never knew was possible. Regina's grip on the dagger's hilt intensified as did her intake of breath.

"Mmmm, I know you feel it, just as I do." The Dark Swan rasped.

At that moment, Emma's choices were clear, rip out Regina's heart and take Regina with her to the darkened oblivion, or honor Regina's trust and leave her unscathed. Emma's actions depended on Regina's own. Regina held her ground, staring into Emma's eyes, unflinching, calm, a pillar of strength. Emma's hand began to reach into Regina's chest, agonizingly slow. Regina didn't falter. As her hand reached its prize her fingers wrapped around it, Regina's lips curved, ever-so-slightly. Emma's touch was warm, gentle, without demands. She stared into Emma's eyes, defying the Dark One, and welcoming Emma.

Emma's hand caressed Regina's heart as Emma returned the smile with a much bigger one of her own. Slowly, Emma withdrew her hand from Regina's chest. "You do, even when the darkness stares you in the face, threatens your life. There is no other like you, Regina. You are my perfect match."

With the Dark Swan's admission, Regina let go of the last vestige of fear. It was this truth, this reality that Regina had struggled with. The reason she hadn't summoned Emma sooner. Regina knew, deep down, that this would be the outcome and how many lives it would change. Emma knew as well, and some light part of her lingered just enough to keep her from allowing herself to be summoned by anyone she might inadvertently harm. She would allow no one control over the dagger who couldn't one hundred percent completely trust her, and she in return.

"Regina, a part of me wants to do terrible things. Wreak havoc on innocent people. Destroy countless lives." Emma stepped so close to Regina that their noses nearly touched, her eyes roamed Regina's face and down the front of her. "Engage in wild and lustful acts and annihilate my prey in the process." Emma's breathing quickened, her fists clenched at her sides.

"If it's fun you want, search out Hook." Regina dared.

Emma laughed, dark and evil. "I might just do that." Emma's finger slid down the collar on Regina's pajamas. "However, I think you know how to be much more fun."

"Emma, don't do this." Regina's tone carried the weight of warning.

"Why? Afraid you might like it?" The Dark One taunted.

Regina steeled her with a look.

Emma looked back into Regina's eyes. "I will do nothing to harm you."

"I know."

"I will protect you with every fiber of my being."

Regina tilted her head. "I don't need protection, Emma."

The Dark Swan bared her teeth in what could be either a sneer or a smile, perhaps both. "I know. That's what I've always admired about you, Regina. You cower for no one. You know the pull of the darkness, Regina, you understand it; you understand me. Your strength of will entices me. You're my equal, and my opposite. You hold within you the beacon to the darkness we both crave." Emma spread her arms wide, tossed her head back on her neck and sighed.

Beacon... "I don't want that darkness, anymore, Emma." Regina spoke softly.

Emma righted her head and gave an evil sneer.

Standing before the Dark Swan, every nerve ending a tingling mass of magic just waiting to be released, Regina searched Emma's face, her blood red lips, slightly parted in a twisted smile, the steady pulse of her heartbeat in her throat, the tangled mass of golden curls falling around her shoulders. Then Regina looked in her eyes. They held the promise of power, of pleasures wilder than any evil she had dreamed up in her old life, they beckoned for her to join. But Regina didn't allow herself to stop there. Behind the mirrors of the Dark One she saw a flicker of light, a steady, golden ember that sparked something stronger in Regina than she had ever before known. She found the light, she found Emma. And in the recesses of her mind, Regina heard Emma's voice, sweet and pure, "Don't let go of the dagger, Regina. You're the only one who can save me." Regina knew, at that moment, she was Emma's counterbalance.

Defying the Dark Swan's words for the truth in Emma Swan's eyes, Regina challenged, "Do your best, Dark One, but I will not let you keep Emma. She's mine."

An instant later, the Dark Swan dematerialized and took flight, swirling her feathers of ash all around Regina before disappearing into the night.

Regina looked down at the bloody dagger in her hand, and smiled.