Okay, I'm gonna make this brief because I don't want to get in the way of the story: this fanfiction was basically written as part of a self-indulgent AU me and my friend made. It's set roughly 20 years in the future, Luke's in his 30s and Layton's somewhere in his late 50s. Also since the games kind of don't have a definite timeline, I'm sticking with an almost modern time... say, flip-phone era? Alright enough explanation, hope you enjoy!

Prologue: A Curious Correspondence

It was a calm, quiet morning. The type of morning best spent on a leisurely walk down the cobbled streets to part the remaining fog, reveling in the cool silence before the summer sun chases it all away. The type of morning where everyone throws open their windows to let in some of the breeze and get the energy of the day flowing throughout their homes. Well, perhaps not everyone.

Luke Triton looked out into the village streets and let out a sigh. It had been quite a few years since he'd moved back to his birthplace in Misthallery, and at first it had been so thrilling, starting as a teacher's assistant at the local college before moving up to full-time English teacher. He'd been so excited, and of course the Professor had been happy for him as well. The two of them corresponded often enough, that no sooner had he heard the news did he rush right down to personally congratulate his former apprentice.

That was the last time he'd seen the Professor in person. Of course, they still corresponded quite a bit through letters; though they could just as easily call one another, the two of them both preferred the old fashioned way (it felt more genuine, as Hershel put it). Luke would tell him all about his students and colleagues, and read with fascination about Layton's continued work alongside Scotland Yard. But after a while, the letters became fewer and further between. For every three Luke would send, he would receive but one in reply. It was painful, feeling them grow apart like this, and after they'd promised each other that they'd be friends forever those many years ago. Luke had tried to organize another meeting for them but it seemed something always came up for one of them.

And that wasn't even his biggest problem.

He got up from the window and shuffled over to his desk, straightening out a stack of papers he had shoved off to the side in an attempt to make it at least look organized. He stared at the parchment paper in the center. It contained just three words, "Dear Professor Layton", and as much as he tried he couldn't think of anything else to put after them.

Five. Five unanswered letters. It had started only a couple months ago, at the beginning of summer, when Luke had stumbled onto a news report about a mysterious bank robbery in London. It had been masterfully done: there were no cameras left working, no prints or DNA to sample, and the only clue they had to the culprit was a puzzle. Written in an elaborate hand on a postcard that had been slipped into the emptied safe.

Naturally, Luke had jumped at the opportunity to mail the Professor about it; doubtless he was already working with the Inspector to try and track down the culprit, but still Luke couldn't help but wonder if maybe, this could be a chance for a reunion? A chance to have master and apprentice together again for one last mystery?

Layton hadn't responded. A few short weeks later he'd seen another report of a similar incident, and two more after that, each time the same troublesome situation, no evidence save for a puzzle on a postcard.

With every new story he had mailed his old friend, and his letters, he feared, had been getting more and more desperate. Why hadn't he written back? Why did it seem like he wasn't doing anything to solve it? He had even called Scotland Yard to see if they had any information, but they refused to release it to him, said it was classified.

He wondered if he should bother calling Layton. He rarely answered his phone (Luke didn't know why a man his age would bother getting a cellular phone, particularly if he wasn't even going to use it) and for some reason he felt like it would be rude to just leave a message for him without speaking to him in person.

Still, he looked back and forth from the mostly blank paper on his desk to the small black phone plugged into the outlet by the wall, wondering for a bit if either of them would be worth a try.

He took a deep breath, trying to fight off the nerves that gripped him. Whatever he was going to do, he was in no state to do it now. For now, perhaps it was best if he made himself get out of the house and enjoy the morning. It would do him well, a quiet walk to clear his head and maybe quell some of the doubts he was beginning to have in his old mentor.

Mind made up, he stood up from his desk, pocketing his phone and slipping on a jacket (he realized he had forgotten to change into his pajamas again last night, and promised himself for the fourth time in a row that it wouldn't happen again). He grabbed his blue cap off the hat rack and reached for the doorknob –

Knock, knock.

Luke blinked, stepping back from the door. Had he heard it right? He stared at it for a second, silently, listening for –

Knock, knock-knock.

There it was! He hadn't been hearing things after all. Quickly, he swung the door open. A short, stout man in a postal uniform stood looking up at him, holding a letter and looking rather inconvenienced.

"Are you Luke Triton?" he asked.

"U-uh," Luke stammered, "yes, I am. What is, er…?"

Luke jumped back as the man thrust out his hand. "Letter for you."

He blinked. "Oh!" he said, taking the letter and looking it over.

"See what it says on the back there, it says 'please deliver in person'. Now I don't know what kind of man this Hershel is, thinking he can just ask for special treatment like that, but at any rate you-"

"Ah, yes, thank you sir," Luke interrupted, "I'm very grateful, now if you'll excuse me." He shut the door, the man still standing in the same spot with his hand held out. After a second he felt guilty, and he opened the door for another moment to add "Have a nice day," before slamming it again.

Luke rushed back over to the desk, shedding the jacket onto the floor. This was from the Professor alright, there was no mistaking his signature wax seal. Grinning with anticipation, he tore open the letter, not bothering to dig through the drawers for his letter opener, and laid it out on the desk to read.

My dear Luke, it said:

Hope you are enjoying your summer vacation so far. Good to hear your job is treating you well, but it's always nice to take a bit of time away for oneself; I'm trying to convince the new dean of that, but he's not hearing any of it. Zero personal days for the summer, and the days I do have for myself sadly don't allow me much time for independent work. But enough bad news for now, I don't want our limited time corresponding to be riddled with negativity.

Let's just focus on the positive, shall we? For instance, I hear Misthallery may be opening up its own university soon. Great news, especially considering they'll likely need a good English teacher, and I believe I can recommend them one.

Luke Triton, English gentleman and puzzle-solver extraordinaire, a university professor… I think it quite suits you. Unless, of course, you're happy with your current college and would rather stay there, in which case I fully understand; university life can be stressful to say the very least.

Oh, but I digress. Lingering on one subject for too long has that effect, all it takes is the first word – nay, the first letter even, and soon the mind begins to wander. Maybe it's time I get back to my lesson plans before Dean Atbash gets on to me for being unproductive. Well, at any rate it was nice hearing from you, and I apologize if I rambled a bit. Love to talk to you more, but as it is circumstances prevent me from seeing you, or anyone who isn't a student or a colleague, really. May be a while before I can write to you again, but until then I wish you all of the best.

Deepest regards,

Professor Hershel Layton.

… Luke raised an eyebrow, scanning each paragraph again several times to make sure he'd read them correctly. Not one single mention of the robberies or of Scotland Yard. He crossed his arms angrily; if anything, it seemed like the only reason he'd bothered to write at all was to tell Luke he was busy and to stop bothering him! And what was this about a new dean, anyway? Whatever happened to Delmona? Well sure, he'd be quite old by now, but still Luke saw no reason to replace him, and he had never heard of this "Dean Atbash"…

Atbash… something about that name sounded familiar to him. He couldn't quite place it, but he knew he'd heard it somewhere. In fact, wasn't it the Professor he'd heard it from? The Atbash… something?

Out of curiosity, he went over to his bookshelf to see if he could find anything about it in the dictionary. He flipped through for a bit, but he didn't see the word anywhere.

He hummed thoughtfully. There had to be something to this. He took his phone out of his pocket, mentally crossing his fingers that his spotty internet connection would hold long enough for him to find –

There it was. The first result led him to a chart on the Atbash Cipher, a substitution cipher where "A" and "Z" are switched.

Was there… had the Professor hidden a code somewhere in the letter?

Experimentally, he tried writing down the letters at the beginning of each line, but after several minutes of switching around letters he ended up with nothing more than gibberish. Maybe there was a clue somewhere in the letter?

It took him only a second to notice it, when the Professor had been rambling about losing track of one's train of thought. The first letter… perhaps he meant the first letter of every sentence? He began to count them out:

HGZB LFG LU OLMWLM

One by one, he filled in each letter with its substitution… but when he finally arrived at the hidden message, he felt a chill go down his spine.

STAY OUT OF LONDON

That was it. No explanation, just… "Stay out of London". What was this supposed to mean? A threat? A cryptic warning of some kind? The Professor urging Luke not to get involved where he wasn't needed? Why would he bother even sending that letter if it's only purpose was to keep him away?!

The young man's head spun with questions. He heaved himself up from the desk and staggered back to the window, flinging it open and hoping that some fresh air would help calm his nerves. He took a few slow, deep breaths, steadying himself. But however hard he tried, that phrase kept barging into his mind.

After another moment, he slammed his hand down on the sill. He was fed up with being kept in the dark; it was time to find out what was going on here.

He whipped out his phone and called up the Professor before even giving it a second thought. It rang once… rang twice… and then a familiar voice chimed in:

"Good day to you, this is Hershel Layton, Professor of archaeology at-"

Luke groaned and hung up the phone. "Damn it, Hershel," he said aloud, "what do you think a phone is supposed to be for?"

He slammed the window shut irritably. Pacing over to an armchair, he looked up the number for the Professor's university and tried that instead. If he couldn't get a hold of Layton, surely someone could.

"Good morning, this is Gressenheller University," came the clear, friendly voice of the receptionist. "How may I help you?"

"Hello, this is Luke Triton," he introduced himself. "I'm a personal friend of Professor Layton; could you try and get a hold of him for me?"

"Oh, I'm sorry," said the woman, "I'm afraid he's out for the summer."

Luke faltered. "W- uh, what do you mean he's out? I – I just received a letter from him this morning, with Gressenheller as the return address!"

There was a pause. "Well, I'm sorry Mr. Triton. It may be that he simply wished his post be sent to his office, because unless he's snuck back into the building to visit the library, I can assure you he has no reason to be here. He requested his summer classes be closed after a certain incident-"

"Incident? What incident?"

"Oh, er…" She sounded as if she'd said something she wasn't supposed to. "Well, it's… the board has asked us not to divulge any details except to the investigators…"

Investigators? "What could be so important as to warrant an investigation?" he inquired more urgently.

"UH…" the woman stammered. "I-I'm sorry, but unless there's something else I can do for you, I'm afraid I have work I need to do. Is there anything else I can help you with today?"

He sighed. Clearly he wasn't going to get anything out of her. "That'll be all. Have a good day, miss."

"You too, sir. Thank you for calling." Click.

Luke slumped back further into his chair, trying to make sense of everything that had happened. An incident at the university? An investigation? A series of crimes? And at the center of all this, a secret message in a letter reading "Stay away from London".

Now this was a mystery if he'd ever seen one.

Before he really realized what he was doing, Luke found himself in his room packing his suitcase. He didn't care what he said; something was definitely going on. He knew he couldn't say for certain, but something inside him told him that the Professor was in trouble. And he intended to do for Hershel what he would have done for him.

He picked up his jacket off the floor and slipped it back on. Glancing back at the desk, he spotted the letter lying in a patch of early sunlight coming in through the window. He grabbed it and stuffed it into his suitcase; he may just need it yet.

He opened the door, taking another deep breath. People were starting to come out of their homes, the low chatter of the marketplace could be heard in the distance. The day had begun.

With the burning awareness that he had next to no idea what he was doing, Luke stepped out into the morning air.

It was dark. Well, not so much dark as simply dim; the light from the flickering candles didn't do much good at illuminating the huge dining hall, but perhaps that was the way he liked it. He sat at the head of a long table, a glass of wine in one hand as he wrote furiously with the other in a small black notebook.

"I wonder," he said to himself. He looked up from his writing and across the table. There was but one other chair, which stood empty. For the moment, anyway.

"No," he said, his gaze cast downward once again, twirling the glass absentmindedly. "No, he wouldn't just rush off without thinking. Even if it's for a good cause."

He took a sip and looked up in thought. "But then…" he argued with himself, "it doesn't seem like him to ignore an obvious sign of distress. No, something tells me he won't be able to help it."

He smiled. It was a smile full of pride, but tinged with a strange sort of amusement.

"After all, that's what a gentleman does."