AN: Okay, so this is a story based on one of the 'Unseen Stories' mentioned in the original series. I decided to write this because, well, the idea of a 'notorious canary trainer' appealed to me. I subsequently decided to be lazy and use Updated!Sherlock, as owned by The Moff and the Beeb, because I find it easier to write for. My first lengthy fanfic for this series, which given that I still haven't watched a single complete episode, was a terrible idea. And no, it no longer has much to do with canaries- although it won't take long to spot the link.

PART 1

We begin with a quote from Arthur Conan Doyle himself: "In the year of '95 a curious and incongruous series of cases had engaged his attention… down to the arrest of Wilson, the notorious canary trainer, which removed a plague-spot from the East End of London." What follows is but one of these cases, namely that of Wilson, updated for the new and much loved Sherlock in the 21st Century.

The Gasman Hacker

Sherlock stamped about the flat in his characteristic bad temper. John Watson sat in an armchair, drinking a mug of thankfully pollutant-free tea (Sherlock had a very nasty habit of contaminating the kettle, teabags, teapot, milk and occasionally the water supply, leading John to seek refuge in Mrs Hudson's rooms for tea-ingredients) and doing some research on the computer. He nodded and said 'Yes' occasionally when it seemed appropriate, but otherwise allowed Sherlock to rant on his latest case uninterrupted. He was just contemplating a mid-afternoon biscuit when Sherlock intruded on his peaceful ignorance.

'-so you'll have to tell Mycroft that I'm not going to, and you- are you even listening, John?'

'Mmhm. Yes, Sherlock.' John took another sip of tea and decided against the biscuit.

'John, so help me I'll kick you out. You're worse than the skull, at least he listens.'

'Uhhuh.'

Sherlock rolled his eyes and threw himself onto the sofa.

John's phone beeped. A text. He checked it:

We've got a case. We are going down to the yard. Get ready now. –SH

John looked up.

'Sherlock, I'm sitting next to you, for pity's sake.'

'You were ignoring me.'

Without another word, the consulting detective pulled on his coat and scarf and swished out of the flat.

At the Yard, they were met by an exasperated looking Lestrade.

'Sherlock, if you do this again I'll-'

'You'll what? Get rid of the person doing all your work for you?'

And with that, Sherlock swept past him and into his office. John and Lestrade followed.

'What was he doing?' asked John in an undertone.

'The bloody idiot keeps turning up before we ask him to. It's like he i knows /i we've given up.'

'He's probably getting tip-offs from Mycroft.'

'Ah! John, come over here. Look at these case reports,' Sherlock interrupted. John walked around the edge of Lestrade's desk and glanced at the case files split-screened across the three monitors. Lestrade spluttered ineffectively for a moment before giving up.

'What about them?'

'They're all the cases of suspicious deaths in the mining industry for the last 3 months.'

'So?'

'So, some of them are connected. I've been meaning to tell the Yard for a while.'

'So why haven't you?' Lestrade broke in, angrily.

'Been busy. Anyway, you can't expect me to do all your work for you.'

Lestrade ground his teeth. 'Someday, Sherlock Holmes, you are going to be arrested for perverting the course of justice, perjury, laziness and any other damn charge I can make stick.'

'Laziness, to the best of my extremely detailed and accurate knowledge, is not in and of itself an offence under law, Lestrade. Oh for goodness sake, are the police really this imbecilic? We can obviously eliminate all those deaths that don't fit the pattern- that's this one with the mines supervisor, she was killed by her husband, it's obvious Lestrade- and these two, the mine workers, that was a suicide pact- do I have to do everything around here?- leaving these twelve.'

'I'm not even going to ask how you knew.'

'Good. Your mind might combust. Just get the husband of that supervisor in the Drrwg Gwelly coal mines and then release the suspect in the Abernethy case.'

Grumbling slightly under his breath, Lestrade sent off a text presumably issuing instructions.

'I want your evidence.'

'Later. Now, look. What's left? These twelve. All dead in similar circumstances. Died of carbon monoxide, carbon dioxide, methane or other gas poisoning. Found with fully functional gas detection devices, so no clues as to why they were poisoned by the gas. No clues as to how or why they died other than the cause of death. The first one was three months ago, how have the police taken this long?'

'We were busy, in case you didn't notice, with solving every crime in England,' Lestrade snapped. 'We don't all have the same free time you do.'

'Excuses, excuses. I was busy too, solving all the crimes you gave up on- which is most of them.'

John stepped in before the argument could escalate.

'But how are they linked otherwise? Could be a coincidence.'

'Twelve men, John,' Sherlock said. 'Please don't be a complete idiot. Twelve men decide to commit suicide, or twelve murderers decide to use the same method, within the space of three months?'

'Okay, so it was murder…'

'How do you know?'

'Is there another option?'

'Easy. They were all members of a gang and fulfilled a suicide pact. They were all members of an amateur electronics society and fiddled with the detectors, breaking them and causing their deaths. They were-'

'Alright, I get the message. So you don't think it's murder.'

'Of course I think it's murder John, keep up.'

'So why did-'

'Keep an open mind, John. There are lots of other options.'

'…Fine. Okay, fine.'

Sherlock turned back to Lestrade.

'So they're all connected. Why?'

'Could be a grudge against the mining company?' Lestrade suggested.

'Nope, they're from three different companies, six different mines. Not local, not a company grudge.'