After I had bandaged Holmes' finger using the medical supplies I always carried, the Auror transported "Jack" into a strongly-bespelled cell from which Lupin assured us he would not be able to escape, and then used Side-Along Apparition to transport ourselves to Minister' Diggory's office. The Minister himself appeared shortly, dressed in a striped dressing gown over spotted pyjamas, to hear our report on the case.

Holmes stated, "It was the memory of a phrase you used, Minister, that gave me the idea. You told us that magical tests had proved that 'no living person' had been in the bank during the time of the robbery. I knew of Inferi from my reading of Wizarding books. Inferi would not need to be released from the morgue, but if previously enchanted and given directions, could leave under their own power. My reading also told me of the Shamir, the worm allegedly used by King Solomon to cleave the stone blocks used to build his Temple in Jerusalem."

"But the Shamir is only a myth!" interjected the Minster.

"Many myths have some foundation in reality, sir," rejoined Holmes. "As I have often told Watson, when you have excluded the impossible, what remains, however improbable, must be the truth. My books did speak of the Shamir as a myth, but the fact remains that we have no other explanation for how the enormous stone blocks were cut for buildings such as Solomon's Temple or the Pyramids with the tools then available. So many of the ancients' secrets have been rediscovered or reinvented that the existence of the Shamir was far from impossible. I reasoned it to be the most likely explanation for the cleanly-cut holes found in the plundered safes. And in fact we found the Shamir and were able to take it away from the Inferi using it, though at some cost." He held up his bandaged left hand, the stump of the smallest finger clearly visible. "The worm is now in Dr. Watson's custody, and he will be happy to hand it over to the appropriate branch of the Ministry for further study."

"Oh, dear," clucked the Minster. "They will be delighted to have it, and of course we will provide the best magical care for your injury. Our Healers will be able to regrow that finger for you, I am certain."

Holmes replied, "That will be most welcome. We were also able to recover the valuables taken in this burglary, and they now rest in Ministry vaults waiting to be returned to their proper owner. Recovering the moneys and jewels taken in the other crimes will be a matter for police, or rather Auror investigation. I leave it in your capable hands."

The Minister said, "And so Jack the Ripper was a wizard after all?"

The Auror replied, soberly, "Yes, though I am ashamed to claim him as one of ours. As Mr Holmes deduced, he used magic to turn his victims into Inferi, but that spell was masked by the magical potential released at even a Muggle's death. We had no suspicion that he was a wizard because he never used a spell to actually cause death. Apparently he preferred," he shuddered here, "preferred to murder his victims more directly. He seems to enjoy their blood."

Later that evening, Holmes was resting following the regrowth of his finger, while I sat lost in thought, wondering whether we non-magical physicians would ever have the capability to reattach or regrow severed limbs. Holmes' motion, as he lit the pipe which was his infallible companion in cogitation, drew me from my own thoughts.

"They will never find that stolen treasure, Watson. I know in whose custody it lies, and he will ensure that it is never recovered. His sinister organization has tentacles throughout the world, and you may depend upon it that those ill-gotten gains are now in some place inaccessible to all the might of the British Crown – even to the little-known magical arm of its government."

"Moriarty!"

"The same. This crime is far too complicated and clever for our Jack. He would never have been able to deduce the existence of the Shamir on his own, track it down and obtain it for his use. Jack was only a tool wielded by a more skilful hand, though perhaps one growing less careful in the instruments it handles. It is far better than he remain in an inviolate prison; he kills for the love of killing, and is lower than the animals who kill only that they may eat. He certainly took the assignment out of lust for blood rather than for gold."

"Moriarty has one weakness that is inescapably bound in with the legitimate persona that is also his greatest protection. As long as he wishes the world to consider him as merely a brilliant mathematics professor, then he must live as a mathematics professor – to the outward appearance, at least. And mathematics professors are subject to visits from students and other mathematicians. No doubt he is wondering today what became of the German mathematician who was shown into his quarters this afternoon, and who so unaccountably vanished before their meeting."

"You, Holmes?"

"No other. I have visited Moriarty's rooms twice before, in other guise. I borrowed the name of a former correspondent of his who never will visit London again, poor soul! The news of his death will not be general for some time, however, but the familiar name was enough to get me past the dragon who guards his rooms. This time I permitted myself the liberty of skimming over his private papers. I had but a brief time with them, but enough to convince me that the stolen money and jewels will never be recovered until we have Moriarty himself in our hands."

His eyes kindled.

"And that time may not be far off, Watson. Moriarty knows of his one weakness and cannot escape it, but otherwise his crimes heretofore have been remarkable for their total success."

"True: you have foiled his plans this time."

"But more than that, for the first time he has bungled. This time he chose a tool inescapably flawed for his use. Even Moriarty would not have been able to control Jack for much longer. His fastidious lieutenant, Colonel Moran, would have had no insight into such a flawed mind. We had to intervene to remove the menace from the streets of London, but had we been able to stay our hand, one day Jack's increasingly insatiable bloodlust would have betrayed his master. They would have killed him, or course, but perhaps not quickly enough – indeed, they have already been too slow to prevent us from capturing their pawn. And like the chess master, we learn something about our opponent from his every move, and from every piece of his we capture."

"But we knew already that they did not scruple to hire the most dangerous men for their fell purposes."

"True, Watson – but in the past, if their pawns were flawed it was only in the moral sense. They have always made a point of getting the most capable man possible for any job. This time, they were forced to use a more deeply flawed piece. That tells us of their increasing desperation. Each time our paths cross, we draw the trap a little tighter. And one day – may it be soon, Watson – the trap will close around them and it will be checkmate!"