Disclaimer: I don't own BBC Sherlock. Steven Moffat and Mark Gatiss are the creators.

No Mercy

John closes the front door and walks into the flat after going out to buy breakfast; a bagel and two cinnamon rolls. His jacket is sodden and water drips from his hair onto the carpet. He wraps his hand tightly around a polystyrene cup.

"A stall was giving out free tea. It's a nice start to a miserable Monday." John says more to himself but it is directed at Sherlock. He opens the bag from the bakery and puts a cinnamon roll on a plate and gets to making Sherlock a cup of tea since the lazy bugger never makes himself one.

Sherlock groans in acknowledgement.

"Sherlock?" Mrs Hudson calls from downstairs, "This letter is addressed to you."

Sherlock meets her downstairs and looks it over. Cheap. From a post office. No stamps, hand delivered. Coffee stain in the corner, carelessness. Sherlock opens the letter delicately and withdraws the contents. It reads:

I hope John likes his tea. It has been laced with an odourless and colourless poison so you won't find it. From this sentence it should be 30 seconds until it takes full effect.

Sherlock looks at John who was just finishing his drink.

"John! Don't drink that."

"Why?" John looks down at his cup and then at the letter in Sherlock's hand. Living with Sherlock means that John can now deduce some situations and this one was simple.

"Oh shit." John curses before his eyes roll back in his head and he collapses onto the floor.

Sherlock looks back at the letter; we will give you the antidote if you tell Scotland Yard to put £150m in this bank account 9427 5413 0826 poison is fatal and will kill him in 2 hours.

Sherlock drags John onto the couch and gets some ice out of the freezer wrapping some in a flannel. He places his head in his lap as he wipes the cold flannel over his forehead. Temperature is at 40oc. Rapid pulse. Occasional shivering despite his high temperature suggesting a fever. He has an hour and a half at the most not two.

The message is cut out of newspaper articles but they weren't as careful as they hope showing that they aren't use to criminal acts. Sherlock goes to the hospital and begins scanning and analysing the envelope. Licked shut. Saliva belongs to drug dealer Victor Lorenzo. 3 sets of finger prints; one belonging to Victor. Other two are petty thieves of no significance. The person who delivered this won't be far away. Person who created this letter is young and naïve, by giving me details of the poison I can track it down. 5 minutes later Sherlock finds the poison. Sodium Monofluoroacetate. John could die in 30 minutes or 3 hours time.

Sherlock half covers John with a blanket and kisses his forehead before putting on his Belstaff and scarf and exiting the flat. The letter has coal dust smudges on the back. The nearest building holding coal would be the disused factory half an hour away by taxi. The building also has accommodation for the workers on the second floor. Sherlock has one objective; find and kill.

As he approaches the factory, lights can be seen illuminating a single room on the first floor. Best way to enter is through the emergency exit although some of the back of the building has crumbled away. There were 4 flights of stairs in total. I shall have to climb up what remains of them and then use the scaffolding. Sherlock runs through his plan a second time then follows through.

As he drifts through the discontinued building like an assassin, pulling himself over rods and flipping over bars like a gymnast. He silently picks up a copper pipe with a rugged edge and holds it by his side when he reaches the ground of the second floor. He peers around a corner and surveys the three men. A bottle of whiskey, half a bottle of water, bags of crisps and sandwich containers cover an upturned coal basket and parts of the floor. Car lights flash through the front of the building so the men pick up their guns and walk down the make shift stairs, a ladder, to meet their visitor.

Sherlock steps out of hiding and walks to the window looking out at the front of the factory. It's dark due to most of the windows being covered by cardboard so Sherlock removes it so he can see out although the torrential rain makes it harder for him to see the men. 2 men step out of the car, one being Jim Moriarty. He seems to be shouting at them. One of the men raises his gun to shoot Moriarty but someone shoots first. Sherlock looks about the darkened room looking for a sniper but another man steps out of the car, Sebastian. Sherlock opens the window a bit and hears the last few lines that Moriarty says,

"Isn't what I pay you enough? I mean really? Scotland Yard aren't going to give you £150m, even they're not that stupid. Now John Watson…he is claimed property and you've poisoned him. In doing that you've just pissed off a man who's exactly like me, maybe worse. He's more creative though, I'm just more dramatic. However his morals keep him on people's goods books, pity." Moriarty looks to the window where Sherlock is and subtly nods his head in greeting, "Now. I would allow Seb to kill you both but you are meant for someone else. You deserve whatever's coming to you." He gets back inside the car and they drive away.

The two men scramble into the factory dragging the man's lifeless body too. One of the men stays on the ground floor with a submachine gun and the other dashes upstairs. Sherlock puts the cardboard back onto the window and stands in the middle of the room, waiting for them. A young man enters the room and freezes as he sees a figure standing in the centre of the room. He fumbles with his assault rifle and shakily raises it.

"Who are you?" Sherlock doesn't answer and takes one step closer.

"Stay where you are! I will shoot you."

"I'm Sherlock Holmes." The gunman gulps recalling Moriarty's words, you've just pissed off a man who's exactly like me, maybe worse…you deserve whatever's coming to you.

"Do you have the antidote?" They young man stands frozen in fear so Sherlock raises the pipe so it's in both hands.

"I…I don't know where it is."

"Does the other man?"

"I think so."

"Think?"

"I…I mean yes. Yes he does."

"So you are expendable?" Sherlock steps closer again and the man grips his gun tighter although he is trembling terribly. Sherlock notices that the safety catch is still on and smirks triumphantly. This boy knows nothing. He twirls the pole around his head and strikes the guys face. The man crawls back, spitting out some dislodged teeth and tries to find his gun which he threw when he was struck. Sherlock stands on his wrist and he cries out.

"Ssshh." Sherlock soothes, "If you can't be silent then I'll have to make you."

Sherlock grabs the pole and thrusts it through the man's neck, disconnecting some vertebrae and causing a flow of blood to spray on his face and coat as he punctures the jugular vein.

One down. One to go.

All the commotion upstairs grabs the third man's attention so he walks up the ladder to the second floor.

"Liam, you ok?"

Sherlock steps into a stream of light coming through a crack from the window so half of him is revealed.

"I'm afraid your 'buddy' has been disposed of."

"Who are you?"

"Dull. You all ask the same questions."

"You? How many people have you 'disposed of?'"

"Let's get to the task at hand shall we Victor Lorenzo; where is the antidote?"

"You know who I am? Ah, you must be Sherlock Holmes. People say you're a machine yet you care so much for that Doctor Watson. John."

The man chuckles and Sherlock's eyes burn with rage. He grasps the pipe harder, his knuckles going white and calculates multiple ways to kill him…slowly.

"I'd say you have 30 minutes left to save him. I'd die before I give you the antidote." Victor continues.

"That can be arranged." Sherlock says menacingly.

The man stops laughing and raises his gun. Sherlock ducks back into the shadows, the spray of bullets just missing him. The man empties his cartridge and goes to reload. Sherlock takes this opportunity to attack. He steps into the light, blood glistening off the pole and he sweeps the man's feet, sending him over. Sherlock stamps on his arm twice, shattering it in two places. Victor drops the gun and shouts out in pain. Sherlock pulls out a knife from his inside coat pocket and twirls it in his fingers. He picks up Victor's gun, putting in another round and shoots both his shoulders and both his knees, immobilising him, then resumes twirling the knife.

"Here are your options: I can shoot every inch of you saving your chest and brain till last so you can feel every bullet penetrate your flesh and bone, I could carve my initials into your chest so the rest of Moriarty's employees will know not to underestimate me or you can give me the antidote now."

Victor stares wide-eyed at Sherlock.

"I…it's in my jacket pocket."

Sherlock fishes through his jacket and extracts the small vial looking over it.

"Know if you are lying to me I will hunt everyone you love and kill them all."

"I swear to you, on my life, that is it."

"You might want to swear on something of worth. Your life is mine anyway and I don't need it."

Sherlock pockets the vial containing a clear liquid and stands up picking up the gun.

"No, no. Please…please. Don't kill me."

"Not such a tough man now are you." Sherlock mocks.

"This is another aspect where you're all the same. You all grovel for your pathetic lives. It's rather boring."

He aims the gun at the man who starts squirming and tears flow down his face as his joints move.

"This isn't for you but do please shut up."

He aims the gun at the wall and shoots four bursts; 1 long burst, 2 short bursts and another long burst. A smiley face is now engraved on the wall. He tosses the gun aside and retrieves his knife again.

"This is for you."

Victor starts begging and pleading again. Sherlock rolls his eyes. He puts the knife in his left hand, grabbing the pole and smashes it into Victor's head. Enough pressure to severely concuss but not hard enough to kill. He opens Victor's mouth and reaches for his tongue, removing it with his knife.

"It's my trophy plus you wouldn't stay quiet. I did say please."

Sherlock looks down at Victor loving where this design is going and he checks his phone for the time.

"Shit. I've got to get to John, pity; I was just starting to enjoy myself. Well, it was nice meeting you." Sherlock stabs the knife through the centre of his cranium, removes it and wipes the blood on the man's clothes. Sherlock takes a picture of his work on his phone and sends it to Unknown before picking up a container of petrol and emptying it over the bodies and around the building. When he's near the entrance he sets it alight and goes to hail a cab.

20 minutes left.

"If you reach Baker Street in 15 minutes I will give you £50." he bribes the taxi driver.

The driver increases his speed and he reaches the flat with 4 minutes left. He ignores Mrs Hudson's questions and dashes up the stairs into the flat and injects the vial into John's basilic vein in his forearm. He sits back but looks at John intensely awaiting signs of consciousness. John blinks a few times and sits up coughing, gasping for breath.

"Oh thank God." Sherlock sighs.

"Sherlock?"

"Hi."

John looks around and sees Sherlock speckled with blood. His eyes go wide and he sits up rapidly causing a wave of vertigo.

"You're…there's blood. Are you hurt?"

"No. I'm ok. It's all ok."

"But –"

Sherlock quickly leans forwards and kisses John, silencing him.

"Well that was unexpected."

"Yes I guess it was. Not good?"

"No…good. What was it for?"

"I guess I missed you."

John smiles at Sherlock and Sherlock smiles back.

"Are you going to tell me what happened?"

"If I did I would have to kill you."

"You wouldn't."

"You're right, I like you too much."

John chuckles and goes to stand up but stumbles still dizzy. Sherlock immediately grabs him so he doesn't fall.

"Thanks." John mumbles rubbing his eyes.

"How about you sit, I'll make us a cup of tea and I'll check you over."

"Ok, thanks. My med kit is in –"

"The third draw down in your dresser. I know."

"Have you been going through my stuff again?"

"Does it matter?"

"Some of my stuff is priv –"

Sherlock quickly turns around and presses his lips to John's again.

"No more questions. I will tell you what you need to know. You need to know you are safe now and that the people who did this have been stopped."

"Can I know who?"

"Some of Moriarty's employers got greedy."

"Oh, ok."

John steps back, "Are you going to make me that tea?"

Sherlock grins and heads to the kitchen; on the way his phone vibrates, a text.

Nice Work. JM and SM

Sherlock smiles, deleting the text and puts his phone back in his pocket. He continues making him and John tea while John phones work saying he's sick. John doesn't know how the blood got onto Sherlock or whose it is but he knows whatever Sherlock did he's thankful for.

...

A/N – Hope you enjoy it :) check out my other stories xox