Disclaimer: This fanfiction is not written for profit and no infringement of copyright is intended. Not beta-read so all mistakes are mine. Note there's some bad language and sexual threats in this chapter- if that squicks you then do not read on. Thanks for their reviews go to Katya Jade, patemaleh and likingthistoomuch. Happy Hallowe'en!

~ BREAKS ~

"So," the ghost drawls, "you must be Watson's beard."

Mary looks at him in amusement, so obvious an attempt at needling making her smile.

"So," she answers evenly, "you must be Sherlock's criminal mastermind- The one who blew his brains out on top of Bart's four years ago, yeah?" She snickers. "Blood spatter looks good on you, Jimmy-boy."

The ghost- Moriarty, she presumes- preens as he looks at her. "You knew?"

She shrugs. "Not until tonight- But then, Sherlock's not the only one can make deductions." She lets her grin turn vicious, runs a hand nonchalantly over the metallic table to her right. She can feel her cannister of salt-iron twisting inside her fist but she daren't use it yet, so she keeps her hand inside her jacket pocket instead.

Best to get an idea of what Jimmy boy's up to first.

"Besides," she continues, "the getting mad at Molly's a dead giveaway- Pardon the pun."

Moriarty's eyes flash white, the atmosphere in the room growing taut.

The air starts to cool and Sherlock's broken slides starts to rattle at her feet.

"That worthless little nonentity has nothing to do with me," he hisses, "And she certainly doesn't make me angry."

As he does so, his form seems to become more solid but that's not surprising- Emotion gives ghosts strength, every bit as much as magic does.

Mary had been forced to learn that the hard way.

"Oh?" she asks, cocking her head to the side and edging towards him. Just a little more information, and then she'll make her move. "You're not jealous?" she asks coyly. "I mean, it looked like you were really, really jealous a minute ago…"

And she shoots him a grin, daring him to contradict her.

One of the glass cabinets to her right shatters, then another, and another. "THAT WHORE CAN DIE FOR ALL I CARE," Moriarty screams, the cold in the room suddenly jumping up to Arctic. A howling gale rips through the place, whipping Mary's cardigan about her and tearing at her hair.

The rage in his voice comes out of nowhere, as does the energy in it; For a moment he's so riddled with emotion that he's entirely tangible and instinctively Mary takes a step back. Tightens her grip on her cannister.

He grins at her gleefully.

"So the stories are true," he says, more quietly, as if his earlier outburst hadn't happened.. "Even a Night Witch has to fear my kind sometimes..."

Mary nods evenly, keeping a closer eye on him.

She cannot allow him to get the idea that he's dangerous to her- Though of course he is.

"You can do things," she drawls, trying to keep her voice just the right side of disinterested. "Anything magical can do things- Even a half-dead little speck of ectoplasm like you." At his smile- he's not buying her act, she can tell- he starts advancing on her and as always her training kicks in.

She refuses to back away from him.

He walks over to her, moves until he's staring her right in the face. If he were still breathing, she'd be able to tell what he had for lunch, he's so close.

He obviously thinks he's intimidating her and my, Mary thinks, but that is an ambitious assumption to make.

"I'm going to make him do it, you know," he whispers. His voice is coaxing, like he's telling a child a secret. "I'm going to hop inside as soon as the veil is thin enough, and then I'm going to make him take her like the worthless little bitch she is."

Mary's mouth thins in distaste and he grins.

"Do you think she'll tell anyone?" he mutters softly, circling her. "Or do you think she'll keep this secret for Sherlock too? Do you think she'll let him apologise and go back to being his little mouse, after he's held her down? Rammed his cock in her? Finally given her what she's wanted all this time- Though not, admittedly, in the way she planned. eh?"

His smile widens- He's warming to his theme now.

Mary silently promises herself a long shower just as soon as she gets home.

"And what about dear Sherly?," he continues. "What will this do to him, to his sobriety? His sanity? Do you think he'd be able to live with himself, knowing he'd done it but not knowing why?

"Do you think he can live with knowing he'd hurt his little morgue mouse and made a mess of her insides? Or would he even care- Does Molly really mean anything to him at the end of the day..?"

Moriarty clucks his tongue. Mary glares at him.

His smile should be grounds for murder.

"I mean, he's so self-destructive, isn't he?" he muses thoughtfully. "He's been a dead man walking since the day he was born. Will he do it in Baker Street, do you think? Let dear old Hudders find him? Or would he come here, return to the scene of the crime, as it were-"

And there, Mary thinks, you have it.

About bloody time: Listening to this was making me sick.

"So that's your play." she speaks over him, grateful to have her theory corroborated, and Moriarty blinks at her.

It's almost as if he can't believe she had the temerity to interrupt.

"I beg your pardon?" he asks with inflated disbelief. "But what is it you think you've guessed about me?"

Mary isn't buying it though: Moriarty's ego has gotten enough of a workout for one night, she's not going to favour him by humouring him any more.

Rather, she cocks her head. Looks at him. Leans right into what would be his personal space and smiles.

She can see he doesn't understand what she's doing and she finds she likes that quite a lot.

"You know what's sad, Jimmy?" she says conversationally. "You know what's absolutely heart-breaking about this kind of work?"

His lip pulls into a sneer. "No," he huffs out. "Please do please enlighten me."

This time the grin she shoots him is every bit as irritating as his. "The problem with this kind of work," she says, "is seeing someone who was God awfully stupid in life and realising that they've remained God awfully stupid in death.

"I mean, you're just so… disappointing, aren't you?"

He gives a gasp of outrage, another cupboard shattering.

This time the entire room shakes but Mary continues with nary a pause.

"Cuz you're supposed to be clever," she says evenly. "You're supposed to be the smartest man in the room. You're supposed to be this criminal mastermind, this Napoleon of Crime. And you have all of this time to think, and to repent, and to muse on why you were such a collossal arsehole in life and yet this is what you waste your time on- Revenge. Revenge on Molly and revenge on Sherlock.

It's actually kind of pathetic, really, Jimmy boy."

She clucks her tongue.

"Shows a terrible lack of talent. I thought you might be smart enough to buck the trend, short-arse, but alas, no such luck."

And Mary does the thing which all of her kind must be able to do in the face of danger. The thing which makes her kind so much different from the other operatives in the dark, shadowy in netherworld in which she used to work.

She laughs.

She laughs long and loud, because she knows she's going to beat this bastard.

She laughs long and loud because if there's one thing the forces of darkness hate, it's to be made light of- Light of any description is anathema to them.

Judging by the look on his face Mary knows she's found her mark, just as she knows she's found her moment. Now what Moriarty is speechless- no, incandescent- with rage is the best time to strike- Lest he gather his wits and slip away while he can.

So with one swift, deft movement she pulls the cannister from her pocket. Flips the lid off sharply, sending it tumbling towards the floor. With practiced ease she runs her thumb along the sharpened inner lip of the vessel, cutting her skin open and letting a single drop of blood spatter against the rim.

The cannister glows as it's being primed, the realisation that he may be in danger finally coming to Moriarty.

She has the pleasure of seeing the little bastard blink.

With a snarl of rage he darts at her- the last thing he should do- and Mary presses her bleeding thumb against his near-solid chest, imprinting him with her will. Her blood.

Her power.

He really should have guessed her power.

She mutters her own personal incantation, the words rising to her lips easily even after all the time she's neglected her magic, and with a single, sharp jabbing she forces Moriarty inside the vessel, sealing the spell before jamming the lid back on. Finishing the incantation and, with it, the banishment.

It really is an astonishingly simple piece of magic.

She fumbles the canister back into her pocket and though she knows nobody else can, she can hear Moriarty screaming in rage the entire time.

When Molly and Sherlock return she concocts a story about the fridges, tells them that one of the freezing units must be malfunctioning and that that explains the cold as well as the cupboards' newfound tendency to shatter open,

She can tell that Sherlock doesn't believe her but before he can say anything she cries off, begging to go home and suggesting she might sue Bart's for trauma, something which at least gets Molly off her back about what the Hell happened. (Of course, suggesting that Sherlock finally ask Molly out for coffee- "Seriously Mols, put the boy out of his misery,"- probably has something to do with it too.)

She walks the (soon-to-be?) couple as far as a coffee shop and then turns towards her bus stop. Checks the timetable on her phone. She makes sure she passes a newly-repaired road on the way and drops her canister into its cement, trapping Moriarty inside it forever- Then she heads home to her bed and her John.

In the years that follow she can still here Moriarty screaming for revenge every time she passes his resting place and she always makes a point of laughing-

Because she knows that he can hear her, and he knows that he's not going anywhere.