It's the cordite which concerns John more than anything, though the Lee Enfield is worrisome enough in its own right. Sitting on the kitchen table, the two seem perfectly innocuous, but he knows that they are anything but. Especially together, and especially in Sherlock's hands.
Sherlock himself is nowhere to be seen. The flat's peculiar feeling of emptiness is evidence enough of the missing detective, though there isn't anything out of place. Just the gun and propellant, ominous additions in this time of turmoil.
John suppresses the nausea in the pit of his stomach, and hides the rifle in his room. (Though the Tans are long gone, the worry of firearms in plain sight lingers, ingrained. Such bone-deep concerns have not been shaken by the adjustment to ordinary life since the ceasefire was called.) The cordite he doesn't know what to do with, doesn't even know why it's here, so he puts it in the press and makes tea, hoping it will help to drive away the lingering fear. (Illogical though the fear may be.)
Settling into his armchair, he produces the newspaper and begins reading it, hoping to find something to interest Sherlock. The family killed in Belfast looks promising, but Sherlock will probably put it down to sectarianism so John decides not to mention it. Maybe something else will come up anyway.
He's studying the coverage of the upcoming elections when his ears catch Sherlock's familiar tread on the stairs. The door swings open, then bangs shut, Sherlock traipsing across the floor and collapsing into a graceless heap on the couch, promptly falling asleep. John sighs, lays aside the paper, and presses his fingers to Sherlock's throat, assuring himself that it really is only sleep before he takes the blanket and throws it over the limp form of the detective. Wouldn't do to let him get cold, especially when he hasn't slept in about three days. (At least this time he didn't faint on the street. It was awkward enough once.)
The evening is wearing on, sunlight creeping across the floor, a golden haze as if the country isn't teetering on the edge of a civil war. (Oh they'd never say that of course, the politicians. But Mycroft said as much in the words that he didn't say the last time he was over, and the occupation of the Four Courts is a sure enough sign of it.) At the thought of civil war, there is too little air in the room and John throws the window open, tempting in the breeze. (God knows there's been enough war in the last few years, in all shapes and forms. How could there possibly be war again?)
Hours pass, night falling across the land. (Across the world, it seems.) John tries not to look at the cordite as he makes soup, but his eyes are drawn back to it, time and again, the half-remembered smell seeming to assail his nose, bringing with it flashes of trenches, of streets and alleyways. Rifles, pistols, bodies falling to cobblestone on bright morning, blood streaking the stone in streams of crimson. Could easily be back, nightmarish reality again. (Surely not though. Surely not.)
Eventually, Sherlock stirs. Groaning, mumbling unintelligible syllables, still half-asleep when John presents him with the soup, too tired to argue about eating. (It's been about three days since any food has passed his lips too. Post-case crash is always bad.)
When the bowl is about half-empty, John works up the nerve to ask about the cordite.
"It's for an experiment," is the hoarse reply, baritone sleep-roughened.
"What sort of experiment could possibly require . . . that?"
"Want to see if chewing it helps me think. Supposedly it's quite successful, and with your attempts to wean me off cocaine . . ." He trails off and sighs, slumping back against the cushions, eyes drifting shut again. The exhaustion is plain to see, but he'll be alright again in the morning. (He really ought to stop doing this to himself, but that won't happen. No point in arguing with him.)
"And the rifle?"
"Murder weapon from St. Stephens' Green. Ran some tests on it while you were out." He cracks a yawn, unsuccessfully stifling it with his hand. "If you don't mind, think I'll go back to sleep."
"Don't you dare think we're finished discussing the cordite."
A slight smile curves Sherlock's lips. "Of course."
John smiles fondly at him, though he can't see it, and pulls the blanket up to Sherlock's chin. For now, at least, the city is peaceful. Nothing to worry about in this moment. (However long that may last, he refuses to think.)