"Hey, what's going on?" came Regina's worried voice from across the street. Robin followed closely on her heels.
Hook's eyes scanned the dark horizon. "The Dark One. It's no longer tethered to the Crocodile."
"What?!" Regina exclaimed. "Where the hell is it?"
Emma's green eyes widened with fright as she slowly spun in a circle. "It hasn't gone anywhere. The Darkness… it's surrounding us."
Everyone looked around as if the simple act of searching would force the Darkness to appear.
A sudden gasp escaped Regina's lips. Black tendrils violently encircled her, releasing blue light like lightning.
"Regina!" Robin screamed.
"I-" was all a terrified Emma could manage, glancing down at her hands, then back up. Barely visible through the wild black tendrils, Regina looked like she was in excruciating pain. But it also looked like she'd already accepted her fate.
"What's it doing?" Robin shouted at Emma over the deafening noise.
Sudden realization dawned on Emma; it was obvious on her face. A grave expression took over her features. She spoke up.
"What Darkness does. It's snuffing out the light."
Emma realized that not only would the Darkness kill Regina, but Regina would die a Villain. The Darkness was sucking out all of the goodness she'd worked so hard to achieve.
"Well, I'm not gonna let it," Robin declared, running fearlessly at the Darkness terrorizing his love.
"I-" Emma tried to stop him, but Robin was already attacking the Darkness. It threw him back as easily as a toddler throws a toy they have grown bored with.
"That's not gonna work on this thing!" Emma screamed at Robin. Her blond curls blew wildly about her panicked face. "The Apprentice told me we have to do what the Sorcerer did! We have to tether it to a person to contain it!"
There was only the slightest of hesitations, a millisecond, before Emma strode, dagger in hand, over to where the Darkness held Regina.
"Emma!" Mary Margaret cried out. David held her back, hugging her close.
Seeing her advance and understanding her intentions, Regina looked horrified. "No!" came her strained voice. It was very hard for her to speak; the darkness was suffocating. Projecting her voice over the noise the Darkness made, sounding like the roars of a thousand lions, was a million more times more difficult. But she had to say this. "There has to be another way!" she insisted.
Emma looked at her, almost apologetically, tears welling up in her eyes. "There isn't." She paused to prepare herself. "You've worked too hard to have your happiness destroyed."
Emma reached out at the dark tendrils, but was interrupted by David. "No!" he exclaimed, in a last-ditch effort. Emma could tell he knew he couldn't stop her. This is what she needed to do. She turned to her parents. Her parents, the same age as her. Her parents, who she'd only known a few short years. Her parents, who'd loved her and betrayed her and loved her again. Intense determination ruled her face. "You figured out how to take the darkness out of me once." Her voice broke. "You need to do it again. As heroes."
"Emma! Emma, please! No; don't do this." Hook closed the gap between the two of them. Emma stared into his eyes, pain evident in hers.
"I love you," she said. The words she hadn't been able to say before. The last loose end she needed to tie up; it was tied now. She forced herself to tear away from Hook. Like lightning, she turned and thrust the dagger into the Darkness.
"No!" protested Hook, too late.
The Darkness left Regina, it gave her up without a second thought. She ran back to Robin and watched, terrified, with the others, as the Darkness claimed Emma. It was a more than unsettling sight; it was disturbing. The Darkness circled Emma with even more purpose than with Regina, the dark tendrils starting by wrapping around her arm, then progressing until it encompassed her whole body.
Regina knew it was very painful, but the only signs of pain Emma was willing to show were a few quiet grunts. It was just like Emma to hide her feelings from others.
After what felt like hours, the Darkness went out in a burst of blue light, taking Emma with it. The dagger clattered to the ground.
On it were two devastating words: Emma Swan.