Sherlock never makes his meeting with Lestrade. That very afternoon as he is heading off to Bart's he receives a text from John.
Stay out of the flat for an hour or two after 6pm. Ending it with Laura. You owe me the privacy. JW
Sherlock is torn between being pleased and bewildered. Of course he wants John to get rid of the harpy as soon as possible. Yet as soon as possible really seems advisable. How can it possibly take an hour or two to tell someone you never want to see them again?
Still knowing John that is probably not how he will phrase it. Sherlock wishes he would though, clean and neat, no unnecessary emotions. Just no more Laura and no more John being not quite John.
Sherlock spends a satisfying few hours at Bart's trying out the effect of various brands of kitchen knives on male and female genitalia. Molly even brings him coffee willingly and doesn't as much as cringe at the gruesome experiment he is performing. She does however try to bring up the text he had sent but to his great relief Sherlock is able to brush it under the carpet with an evasive 'oh, that, forget it, it's being dealt with. Are you sure you put two sugars in this?' Waving the mug of coffee in the air.
Returning home from Bart's at half past seven Sherlock hopes he has given John enough time to deal with his now hopefully ex-girlfriend. He wonders if he should try to take John out for dinner to cheer him up or just leave him be. There is there is silence in the flat so he assumes that at least the offending woman has departed.
It is a surprise to find that the kitchen is in a complete state of disarray. A chair is upturned and the pile of papers which had previously resided on its seat are strewn across the floor. A broken wine bottle lies among them and its contents are splashed in sprays and pools among the papers. More disturbingly there are darker thicker stains which are clearly the result of someone waving a bleeding appendage around. Sherlock doesn't need his deductive powers to tell who has most likely been doing the bleeding. It's become a too frequent occurrence.
That uncomfortable churning feeling from before returns to Sherlock's stomach and he has just opened his mouth to call out for John when the sound of retching comes from the bathroom and he throws himself around the table, reaching the bathroom in record time.
John is on his knees in front of the toilet struggling to breathe as he retches into the toilet. He is drenched in red wine and smells appalling but the blood flowing from a deep gash on the side of his head is what catches Sherlock's attention.
"John, what happened?" he pushes a towel against Johns bleeding head forcing the man to sit back. Sherlock cringes at the stupidity of the question, he knows what happened really, he just hopes that having John tell him will be quicker than having to deduce the details.
"She brought wine, she didn't get it, so she brought wine" John winces and shies away from Sherlock's touch. His eyes are unfocused and Sherlock is seriously beginning to worry about his flatmate's health. John is no orator but he is usually more articulate than this.
"John, are you hurt anywhere else?" Sherlock asks as he frantically runs his hands over his friend's shoulders and neck checking for any worse injuries than the bleeding gash on his head. John carefully lifts his hands up for Sherlock's perusal revealing a pattern of deep uneven cuts across his forearms. So that is the cause of the blood splatter, yes it fits with the way John will sometimes throw his arms up to emphasise a point when he's really angry.
"From the bottle" John states calmly "It hurts." He adds, his voice wavering uncharacteristically but he steels himself against both the pain and the sight of the blood dripping down his arms, after all, freaking out is hardly going to help. Unfortunately his determination is not enough to keep the shock and concussion at bay and he promptly passes out slumping into the arms of his worried flatmate.
"Shit…" Sherlock curses "John wake up, look at me." He pats the side of John's face like he's seen John do before when one of the new yarders had fainted at a crime scene. It had worked then but it isn't doing the trick now. John's eyes remain stubbornly shut.
Sherlock is frustrated to hear the hint of panic in his own voice as he calls for an ambulance and puts them on hold, despite their insistence that he keep talking to them, so that he can shoot off text messages to Mycroft and Lestrade.
Need your help, John's been hurt, private room and visiting to his brother
Arrest John's girlfriend for attempted murder as soon as possible SH to Lestrade
Mrs Hudson comes running up the stairs with surprising speed behind the ambulance medics looking very worried. Standing at the door to the bathroom with hands clasped over her mouth she watches as the medics pry John's unmoving body from Sherlock's panicked grasp. She offers no direct comfort merely standing there watching as the medics wrap John's arms in bandages and lift him onto a transferable gurney. They pinch and rub at John calling his name and get the response that Sherlock had failed to. John opens his eyes briefly and mumbles his name and address obediently before closing them again.
"Sherlock, what happened?" Mrs Hudson asks softly but is silenced as Sherlock's phone chimes to life and he picks it up.
'Lestrade, did you not get my message?' he barks angrily as he follows the medics out of the bathroom. 'John broke up with his girlfriend today, I returned home to find him concussed and bleeding hence you should arrest her as soon as possible…. No you don't need John's testimony, mine is quite good enough' He forcefully ended the call in time to climb into the ambulance behind John. Mrs Hudson stood on the pavement, stunned into silence and watched as the ambulance pulled out and made its way to the nearest emergency room.
John comes to again in the ambulance but he's confused and unfocused. One of the medics tries to get him to breath in an alcometer and Sherlock snags it out of her hand angrily. 'He's not drunk, he's concussed. Why do you think he passed out?' he growls at the poor woman.
'I don't think there is any doubt that there was alcohol involved in whatever fight he found himself in. Seeing as you're not equally drenched in wine I assume it wasn't with you?' She spits back at him as she grabs his wrist to pry the alcometer out of his hand.
'Disturb us again and we will have the ambulance stopped and you removed. You are not our concern, your friend is.' She says with a frown and though it irks him Sherlock allows her to press the implement against John's lips. He is childishly pleased when John does not have the strength to breath long enough to give a reading and she is forced to take a blood sample again. He knows he shouldn't be pleased with this but in a way that it seems that John, even injured and confused is agreeing with Sherlock and putting up a bit of a fight. At least that is how he will interpret it, because that would be nice, and the alternative is something he prefers not to think about.
Instead he sits down, and shuts down. His mind is filled with information that can inform this scenario. There are statistics on head trauma and blood loss. There are legal accusations and defences related to physical abuse of various kinds. There are conviction rates and, finger prints, and word of mouth and as long as he keeps John out of it he can turn this into a case. It will be dull and boring, so obvious it doesn't even deserve a rating, but because there is so much evidence it will take some time to file it all, and boring or not, it is the first case in which a conviction has ever really mattered to Sherlock.