Sherlock stands near the edge in shock. He had seen death before, as well as suicide, but this is something he never thought that he would see.
Jim Moriarty, dead. Lifeless on the roof in a pool of his own blood. Sherlock glances around for any sign of the snipers Jim had mentioned, but to no avail. He turns back to the ledge when he hears it. A soft laugh, slow and dark. His head whips around to look at where the sound seemed to have come from only to see the nearly empty roof.
He turns back to the ledge, afraid to peer over and look at the steep drop when he hears it again. This time, the laugh seems to come from all around him. He searches the roof again for any sign of the owner of the mysterious laugh. Out of the corner of his eye, he sees a flash of dark hair. He turns around and sees a young woman of about twenty standing near the door to the stairs.
Her nearly black hair hangs in soft, tangled waves to her waist, and her knee length white dress almost blends in with the wall that she leans on. She looks up at the sound of Sherlock's footsteps and smiles slyly at him. He stands a few feet away and eyes her quizzically.
"Hello there." She says. Her voice is gravelly and rich, with an almost masculine quality to it.
"Do I know you?" Sherlock inquires. The woman smirks, pushes off of the wall, and walks slowly towards Sherlock.
"Nope." She grins. It is wild and feral, and sends chills down Sherlock's spine. "But I know you."
Sherlock quirks his head to the side. This seems to please the woman, as her grin widens and she flits over to the ledge and peers over.
"Long way down." She breathes. "These buildings just get taller and taller every year. Not that I get the chance to see them very often." Her voice has taken on a wistful tone and her gaze has shifted skyward.
Sherlock watches this strange woman grab her hands behind her back and begin to rock back and forth on the balls of her feet. She looks over her shoulder at Sherlock and beckons him over with a flick of her head. Sherlock reluctantly complies.
"It's strangely beautiful, don't you think? All of those people rushing about down there, completely unaware of what you're going to do."
"And what am I going to do?"
"Jump. Isn't it obvious? That's why I'm here."
"Because I'm going to jump?"
"No. Because you're going to jump for them. For him." She turns her head and fixes him with a pointed stare.
"What do you mean?" Of course, Sherlock knows exactly what she means. He only wants to hear the words out of someone else's mouth.
"This isn't an ordinary suicide. Actually, this isn't suicide at all. This is sacrifice." She looks up at the sky and smiles. "Noblest way to die, as deaths go."
"How do you know all of this?" She throws her head back and laughs again, dark and rough.
"Because I am you." He throws her a skeptical glance. "Well," she amends, "I was you. I died for someone else." His gaze shifts from skeptical to incredulous.
"Do I look that foolish to you? You're not dead. You can't be. That would be impossible." She rolls her eyes.
"So young. So naïve." She reaches out and strokes his face, a gesture he flinches away from. She makes a disappointed noise in the back of her throat.
"Naïveté aside, it is a statistical improbability for you to be dead. If you are, in fact, dead, the how are we talking to one another? How can I see you? How are you able to touch me?" She smirks at him.
"I think I may have found the one thing that having a big brain like yours would get in the way of."
"And what is that?"
"Believing."
He looks over at her angrily. She merely smiles and steps up onto the ledge.
"Fine. If you want proof, then I will give you proof." She lifts one foot and hovers it above the empty space in front of her. Looking back at him and grinning, the woman steps out into the air.
She carefully places her feet one in front of the other, almost as if she is a tightrope walker, suspended thousands of meters in the air.
She stands out over nothing, looking at Sherlock with her peculiar feral grin. She walks just as carefully back to the ledge and sits gracefully.
"Believe me now?" Sherlock nods dumbly, and she lets loose a laugh that breaks Sherlock out of her reverie.
"So, you are dead, and you have come to me. Why?"
"To help. To let you know that you are doing the right thing. To let you know that it will be worth it."
"If I can save him, anything is worth it." He says this with such fierce determination that she can't help but smile.
"Good. Then, there is something else that you should know. Sacrifice, being the noblest of deaths, offers you a second chance, should you choose to take it."
"What do you mean?"
"I mean what I've said. A second chance. You can come back."
"If you sacrificed yourself, then why didn't you take your second chance? Why did you give it up?" She looks startled for a second, but quickly recovers.
"I was in pain. My life was never very happy, you see. I was trapped inside a prison of my own mind and I was constantly suffering. And, when offered the chance, I realized that there was nothing left for me here."
Her eyes had misted over and she jolts when she feels a gentle hand on her shoulder. She looks up into the understanding eyes of a dying man, and quickly wipes away the tears that had gathered.
"Thank you." He whispers. She nods slowly. Standing up and crossing to the perpendicular ledge, she lets out another laugh. This time it is higher in pitch and more carefree. She abruptly turns to face Sherlock.
"He's almost here. It's time, Sherlock." He nods almost imperceptibly. She walks to him and takes one of his hands in hers. "Stay strong. It will be worth it."
She lets go of his hands and walks back to her ledge. As she puts one bare foot on the ledge to stand on it, she hears his voice from behind her.
"You never did tell me who you were." She smiles at the curiosity burning in his eyes. Now standing fully on the ledge, she turns to face him directly.
"Bertha." She replies. "Bertha Mason." She smiles sweetly at him, spreads her arms wide , and lets herself fall backward. Sherlock runs to the edge where she fell and looks over, but she had vanished.
He hears an echo of laughter, low and dark. He smiles wanly and turns back to the street just in time to see John's cab pull up.