A/N: OK, folks, buckle up as Sherlock and Molly put very different plans into action in the wake of Moriarty's manipulations during TRF.

Eighteen Hours Ago

"You're wrong, you know. You do count. You've always counted and I've always trusted you."

Something was wrong, something was terribly, profoundly wrong. Even more than when he'd been in the lab earlier, when she'd tried to reach out to him, she could see the sadness in his eyes that the darkened room did nothing to hide. And his voice - Molly stared up at him. "What do you need?"

Sherlock stepped closer. "If I wasn't everything you think I am, everything I think I am, would you still want to help me?"

"What do you need?" she asked, proud of the steadiness of her voice as he stepped closer, closer, stopped directly in front of you.

"You," he said simply. Profoundly.

Oh how she'd both longed and dreaded hearing such a confession from him. She closed her eyes briefly, then opened them as he explained exactly how much trouble he was in.

You were right. I'm not OK.

As Sherlock detailed the manner in which Moriarty's noose was tightening around him she felt the stirrings of a rage so incandescent that she'd had to take more than a few deep, steadying breaths to help calm herself. And when he finished, instead of trying to release it or box it up, she held onto it, barely reined it in, vowing to release it when it could benefit both Sherlock and herself - and ensure that Jim Moriarty paid for his crimes.

Molly, I think I'm going to die.

No, she vowed.

Not on her watch.

Sixteen Hours Ago

Two hours later she was back at her flat, pacing. Could she do it, could she actually do what she was contemplating, what had been in the back of her mind ever since Sherlock had asked for her help? He'd left her on her doorstep only two hours ago but it felt like days, weeks, months as her mind sped and spun until her head ached and she barely remembered who she was any more.

Could she do it?

She drew a deep breath, let it out slowly, hugging her arms to herself as she remembered the soft, fleeting kiss Sherlock had placed on the corner of her mouth before leaving, and her resolve hardened, the rage exploding from where she'd banished it.

Whatever it takes.

She pulled out her mobile. Hesitated not a moment before opening her contacts and selecting the one number she'd sworn never to use again - but hadn't been able to bring herself to delete.

She held the phone to her ear. Listened as it rang. And rang. And rang.

Just as she was about to give up in despair, she heard his voice.

"Hey, Molls, is it a cold day in hell already?"

Fourteen Hours Ago

Molly once again found herself pacing nervously up and down the length of her flat, hands twisting together as she waited.

And waited.

What if he didn't come? What if she was putting herself through all this for nothing?

A series of short, sharp raps on her front door brought both her pacing and her whirling thoughts to a standstill.

Taking a deep breath, Molly forced herself to cross the room and open the door.

"Good golly, Miss Molly, don't you look ravishing!"

Molly forced what she hoped was (but knew probably wasn't) a seductive smile on her lips as she shrugged her shoulders and allowed the red satin robe she was wearing to slip to the floor. "I've been waiting for you," she said breathily. "Thank you for, um, coming." She lowered her eyes coquettishly and toyed with the black lace edging her bodice.

Jim Moriarty smirked at her weak attempt at innuendo, stepping jauntily into her flat as if he owned it, hands in pockets and looking as if he hadn't a care in the world. And why not? Molly thought bitterly. He was about to get exactly what he wanted from Sherlock - or so he believed.

Not on my watch.

Silently reiterating her earlier vow, Molly glanced around the quiet street from behind her half-opened door, curious to see if he'd done as she asked and actually come alone. Not that it mattered; even if he had an army of footsoldiers standing on her street, none of them would be able to stop her plans once they'd been set in motion.

Even if she was killed in revenge, it would be too late to save Jim Moriarty and that would be more than enough to satisfy her.

Her, and the ravenous beast that dwelt within. The one she'd kept locked away, deep, deep down in the darkest, coldest depths of her psyche. She'd freed it only three times in her life; the first time unknowingly, the second time unthinkingly, purely out of self-defense, and the third time unwillingly. Because no matter how she tried to suppress it, to keep it contained, the damned beast within needed to be freed periodically lest she lose complete control and up like her sisters.

A fate too ugly to be borne; she'd rather die.

She supposed she should be grateful to 'Jim from IT' for giving her this timely excuse to free her personal inner demon.

But she wasn't, and never would be. Not when Sherlock's life was on the line.

"Oh, no worries, Mollywobbles, I came alone," he said with a smirk as she automatically closed and locked her front door, her troubled thoughts plaguing her while she did so. "As requested. Oh, I did have my men check things out before I arrived, make sure I wasn't walking into some kind of ambush." He flashed her a toothy grin to show how not-worried he was about that possibility.

Of course he wasn't worried; why should he be? He'd already taken her measure and dismissed her as harmless.

Well, that was his mistake. It was almost time for the shark to meet a predator he never could have anticipated - but first, she had to try one last time to get him to change his mind.

She walked up to him, trying not to feel self conscious in her skimpy, lace-trimmed satin negligee set. "I'll do anything to save Sherlock," she said bluntly, stopping in front of him. "Anything."

"Never would have guessed," he scoffed, reaching out to pluck at one narrow red shoulder-strap. "What makes you think throwing yourself at me will change my mind, hm? Or are you willing to do more than just sleep with me?" His voice, his eyes, his very mien darkened, as if a shadow had fallen across his face. "What else do you have on offer besides your pathetic little self?"

She tried not to flinch at the insult, but the flash of glee in his eyes told her he noticed it anyway. Fine, then; no more beating around the bush. "Whatever you have planned for Sherlock, call it off."

His answering grin was cold. "And if I don't?"

Molly raised her chin defiantly. "Then I won't have any choice but to stop you."

Jim's eyes flashed with something almost like admiration. "And how, exactly, do you plan on stopping me from doing anything I want?" He stepped closer, crowding into her personal space, running a flirtatious hand up her arm then suddenly grabbing it hard, above the elbow. "Hm, Molly, love? What makes you think you can make me do - or not do - any little thing I want?"

She stared at him, willing herself not to look away - there! What she'd been waiting for! The faintest quivering of his nostrils, the slightest wrinkling of his brow...the noticeable tenting in the front of his trousers.

"Please leave him be. Call off your plan. I'm begging you, Jim. Please." For all of our sakes'.

"No."

Molly let out a ragged breath. Damn him, he had no idea what hell he was about to unleash upon himself.

Deep inside, the predator stirred. Swam to the surface, gaining in speed as Moriarty's eyes glazed over. Molly easily pulled her arm out of his grasp. Pulled him closer to herself. Pressed his head to her shoulder, heard him inhaling deeply, felt the shudder of his body against hers.

When he raised his eyes, those soulful (she'd once thought) dark brown eyes, she smiled, pulling him even closer and pressing her lips to his.

Giving him the kiss that would seal his doom.

End note: To everyone who has been reading and reviewing, my thanks. Things get, hm, very dark for Mr. Moriarty in the next chapter. That's when the fic will live up to the "horror" tag (at least, I certainly hope so). And a shout out to the folks in the Sherlolly discord for helping me figure out the timeline for this part!