Behind the door is: not a lecture hall.

It looks kind of like the fancy box seat areas in a sports stadium, if she's seen those, which she probably hasn't outside movies.

But she probably isn't paying attention to that anyway, because the facing wall is a huge picture window looking out on a galaxy, at maybe a sixty-degree angle to the galactic plane.

Her first thought is that this is the fanciest A/V setup she's ever seen and that they picked a great image to show it off. Then she realizes that the room being this big makes no sense with the building layout and walks in, staring around at everything.

It's laid out like a skybox, complete with seats; there are three loose rows all looking out toward the galaxy. Fancy seats, looks like leather.

The side walls are some dark wood, and go well beyond the wall she walked in through. One wall has a row of three minifridges under a long wood table matching the walls, and there's a sink and row of glasses.

The window has no internal frames breaking it up and looks flat, not convex. There's a thin railing a few inches away that keeps you from walking into it by accident, but it doesn't block access.

No other doors are visible.

Woaaaaah, TARDIS room, wicked. She pulls out her phone and snaps a bunch of pictures because she's absolutely going to doubt her own memory of this later. Then she opens the mini fridges and tries to turn on the sink, mostly just to convince her brain that this isn't a videogame environment and can be interacted with.

The sink has water, in multiple heats. Two minifridges have booze, the third has snacks - cheeses, fruits, and crackers, all prepared like for a fancy party or a catered corporate luxury box. (She doesn't see any meat.)

The door slowly swings shut behind her, which she may or may not notice.

She does notice, after it's already shut, and has read enough stories that even though she is not anywhere close to done exploring this place she immediately goes and checks whether she can open it again.

She can! It even opens to the same place it opened before. The door is entirely well-behaved. (Other than the part where it opens from a hotel corridor in New York to a skybox looking out over a galaxy.)

Okay, cool, not lost in the infinite multiverse or trapped in the faerie realm or whatever. She lets it shut again.

"Hello?" she calls. "Is anyone in here?"

There is no answer. There's also nowhere a human could plausibly be hiding, but that probably wasn't what she was expecting anyway.

Whatever caused there to be minfridges with recognizable food and booze must have encountered human minifridges and food and booze at some point and be the kind of entity capable of imitating observed phenomena, but that's about as far as she can speculate with any confidence. 

She goes up and stares at the galaxy window and tries to identify the galaxy depicted and whether it's a true-color or false-color image.

It's a true color image of a six-armed spiral galaxy, so definitely not the Milky Way. It doesn't match Andromeda either. She can't immediately identify it, so it's probably not one she's seen before?

Does Google images have anything like it? Assuming her phone even has signal in here; she might need to stick it out the door into a spacetime that's definitely contiguous with a cell tower.

She does not have signal while the door is closed, but it can connect if she leans on the door. This isn't too helpful, though; Google image search mostly just gives her artist's depictions of the Milky Way.

If she keeps the door open for a while, some of the other people headed for the tumor growth presentation will probably come in.

Good; maybe one of them will know what the fuck! She feels bad for the presenter, though; this is a hard act to follow and there's no projector setup. She holds the door for the first batch of biologists and wonders if any of them will be brave enough to eat the mysterious fridge food.

She may notice, while trying to look up images, that the official start time of the presentation passed while she was poking around. There is not a crowd gathered in the hallway like you might expect if the door to the room was blocked.

There are, however, people showing up slightly late. The first one narrows his eyes and looks at his phone while walking further down the hall (probably he assumed this was the wrong room). The next two, however, (a grad student and his advisor) actually look through the doorway.

The guy blinks at the galaxy, and the fancy seats, "That does not look like the room that was here this morning. What the hell?"

The older woman is a little slower to react but nods in agreement with that last part.

"I have no clue! It was like this when I got here and it's bigger on the inside and for all I know it's vacuum on the other side of that glass, though that seems kind of unlikely even given how unlikely the rest of this is."

"That's..." He trails off. Apparently he can't decide what that is. Eventually he goes in and knocks on the window, which doesn't make much noise.

His advisor looks kind of shell-shocked for a bit. Eventually she asks Brenda, "When did you, find, this? Just now?"

"A few minutes ago? I'd suggest asking the people who run the hotel what even, but honestly I'd be more surprised if they knew than if they didn't. I'm thinking maybe I should camp here until whoever did it shows up, and also put out some emails to all the physics people I know and get them in here with instruments. . . . Ideally starting with a Geiger counter. Based on the gravity we're still on Earth, at least."

"I probably know someone... maybe not a physicist but at least a radiology researcher. Let me check."

The other guy is examining the minifridges.

"This is exactly like fancy corporate box seats, but instead of football it's a galaxy. Someone has a weird sense of humor."

Then he notices no one's mentioned names. "Uh, I'm James Marston. That's Professor Kissenten, she's my advisor."

Professor Kissenten distractedly says, "Call me Shirley and don't make the joke," before going back to searching her email contact list for @nyu.edu names she remembers.

Brenda knew a physics major who graduated a couple years ago and got a job in aerospace somewhere in the city; she digs him up on the alumni directory and sends a "Hey remember me, come see this". 

"Should someone be getting the New York Times or should we wait for the physicists? I'm not sure I'd have anything helpful to say to a reporter if we had one. Oh, and we should check if time is doing anything funny, can you start your stopwatch at the same time as mine and I'll go outside and shut the door for a minute?"

James gets out his phone and gets his clock app in stopwatch mode. "Ready when you are."

Shirley has also sent an email. "I imagine the reporters would think it was a prank. Honestly, it still feels like a prank to me."

"I'm just glad you can see it too, honestly; I was about to start wondering if I had lost my marbles and the jar they came in."

To James: "On start, three, two, one, start." And once they've both started she goes out the door, waits ten seconds while watching the inside for signs of time shit, shuts the door for another ten seconds, then opens it again and goes back in to compare times.

Time seems to have progressed completely normally during the test. James's stopwatch matches Brenda's to within the centiseconds margin of not-quite-simultaneous button-pressing.

"Okay, so spatial but not temporal nonsense. Which is good, I guess? Oh, hey, does anyone think I should not try to disassemble the sink and see where the pipes go. I would also support a party going to the hotel staff and asking for permission to put a hole in the wall of the next room over but I think someone with more clout than me should do it." There, that's a polite enough form of chickening out of talking to an authority figure.

Shirley blanches slightly. "I'm not sure I have enough clout for that either. Maybe a conference organizer... Someone from the organizers is usually in the talk, to coordinate. We can check the next room over, except... where are the people who should be in this talk?"

". . . Okay so this is going to sound bonkers but I think our hypothesis space should be really really big right now. What if, some people, when they open the door they get this place, and when other people open it they get the room we were all expecting to get? Can you try texting someone who was going to be at this talk and isn't here and see if they're currently watching the talk like nothing is weird?" Deliberately trying to make someone's phone go off during a talk feels like a huge social norm violation on par with asking permission to knock a hole in a wall, but this situation justifies a lot of things.

James volunteers. "I'll text Steve, he got ahead of us so he should be here."

It transpires that Steve is indeed in the room they were all expecting to get and was wondering where the other two had gotten lost to.

"Should I try opening the door?", James suggests.

"Yeah! If you're not back in five minutes I'll open it from the inside for you; I've gotten this one every time. Oh, and we should swap phone numbers first just in case."

"Good idea."

They do. He steps up to the door. Looks at for a minute, a little off-balance. Grabs the handle and pulls. See stars.

"Looks like it works fine for me."

"We should get one of the people in the seminar room to come out. We should get one of the people in the seminar room to come out while I'm holding the door open."

James nods enthusiastically and starts composing a text.

Shirley, however, is old, and has seen many grad students attempt many stupid things. "I think we should wait to test something that seems likely to fail. It may fail dangerously."

James stops typing and deflates a little.

(A few blocks away, in a law firm where two people happen to know magic exists:

"Tee, in here, I have questions to ask you."
"Hmm? Sure, one sec."

He shut the door behind him. "What's up?"
"There's something magic a few blocks that way. Not moving, at all. At a guess, it's in the convention level of the hotel on that block."
He gestures and whistles, then raises his eyebrows.
"That could get messy. How long?"
"About ten minutes so far. No motion at all unless it was while I got up to call you in."
"I'll wrap things up and go look into it. You coming along?"
"This case won't wait, though the curiosity is going to kill me."
"The responsibilities of seniority..."
"Just go.")

Brenda is very easy to talk out of doing things that might rip a hole in the universe or glitch someone into a wall. Instead she sits in one of the chairs and writes down everything they've observed and, in a separate section, everything they've inferred or speculated, and shares the document around to anyone who wants it.

James suggests trying to open the door to the normal room from this side, which doesn't seem likely to rip a hole in the universe if it fails. Well, technically the weird bigger-on-the-inside room is arguably already a hole in the universe? But not a destructive one, and it's stable. Shirley doesn't think this sounds like a particularly dangerous idea.

"What, like go outside and shut the door and open it again but this time specifically hoping to get the seminar room? Oh, and I'm Brenda, by the way, pleased to meet you all independently of whether these are good circumstances or not."

"Yeah, something like that. It might not work, but it seems safer to try. Also the the dangerous experiment will run itself as soon as the talk ends, and on reflection that is in fact scary and we should investigate ways to not do that."

Shirley volunteers, "I haven't tried to open the door, maybe if I try for the normal room?"

"I think a couple of us should try it while wanting both ways, to see if it's person-based or timing-based or responds to intent or what. Also there should always be someone in here so we don't, um, lose contact with it."

James is slightly pensive. "That... might instead mean that we lose contact with whoever is inside. I mean, probably not, but."

Shirley interjects "I think Brenda tried that experiment already, before we showed up. While whoever's inside entered the room normally."

"Oh, right. Okay, yeah, that's not a new risk, and losing the opportunity would be bad. The experimental protocol seems good enough to me?"

"Okay. I guess I can go first, since I suggested it? Unless either of you would rather."

"Sure. I'll go inside, you open the door?"

"Okay."

She does the thing, twice, first concentrating on wanting the room with the galaxy and then on wanting the room with the conference talk.

This works perfectly both times.

Aaaaaaa it's reading her mind! It's not that she has any dark secrets, but that's much more--sophisticated, complicated, agentic--than she had been modeling this phenomenon as being. The computational power involved in reading the neural activity in her mind and interpreting it as preferences about the state of the door is . . . she's getting ahead of herself. That would happen one time in four even if it's completely random. She mentally goes through the first twenty digits of pi, aiming for the galaxy room on even digits and the seminar room on odd digits. She only opens it a few centimeters each time, just far enough to see which room she got, but she's still worried about annoying the people who are learning about tumor growth factors. Hopefully they will understand once it's all been explained.

It is definitely reading her mind and giving her the room she is aiming for.

That's so convenient but aaaaaaaaa. Also she was definitely trying to get the seminar room the very first time, when she found the galaxy room, so what the heck. Not that she was necessarily averse to finding this instead; in fact, given that it exists, she's quite glad she knows about it. She tries one more time, doing her best not to have any expectations about what's behind the door and not to give a damn what result she gets.

The result is: galaxy room.

This time she actually opens it all the way and walks in. "Okay so it's definitely reading my mind about which room I want, which is a separate kind of totally unexpected from the space-warping thing, and I get this room if I'm not aiming for either one. Does someone else want to try?"

James is still in the weird room, so Shirley offers first. "I'll give it a shot. Going to try not to expect anything for the first try."

Surprisingly, it opens to the talk.

"Huh."

From the inside, this just looks like the door not opening. But she only leaves it briefly.

For the second try, she tries to get the galaxy room. This works.

"When I tried not to aim, I got the lecture hall. But then I tried for this room and got it."

"So maybe it has a sort of default per person and overrides it if we're trying for the other one. We should find out what happens if two people each have a hand on the handle, unless that sounds dangerous?"

"I guess that's probably more dangerous than a single person not aiming. But probably not much more, I say go for it."

James just shrugs. "I volunteer to stay in here."

"Alright, the two of us can go if that's alright with everyone." She's very lucky this is happening now and not when she was a tiny undergrad too scared to suggest anything to a professor.

What happens with both of them touching the door, Brenda wanting the galaxy room and Shirley wanting the conference room?

They get... galaxy room, apparently.

James is wandering toward the minifridges, but has a suggestion. "Maybe we should get a larger sample size. Like, ten?"

"Ten seems good; should we just go stand in the hallway and bug people? Also we don't know what your default is yet."

"Oh, that would make sense as well. But I was thinking that we only have a single sample per person for not aiming, and they're different. That could be random variation."

"Yeah, definitely. I'll go do a bunch more attempts--though if it keeps being the same I might have a hard time not expecting anything--and then you can try." She suits action to words, opening the door repeatedly with her mind as blank as she can make it and recording the results as a series of characters in the shared doc.

In ten more attempts she gets the talk eight times and the galaxy room twice, shuffled around in no noticeable pattern. (In order, the talk x4, galaxy, talk x2, galaxy, talk x2.)

Shirley also tries and gets the same result; the galaxy room twice and the talk eight times, shuffled.

"So it's probably random unless we're both the same kind of bad at not wanting anything."

What does Brenda get if she tries wanting the conference room but expecting the galaxy and vice versa? It's a bit of a brain contortion but she can do it with a little setup time.

She gets the galaxy. If she tries some more, she'll get the conference room once out of ten tries.

Possibly she's imperfect at putting her brain in specific states and possibly the room is imperfect at reading her mind when she's doing weird things with it.

"Does anyone have a string? I want to see what the range is on the mind-reading."

They search their pockets and bags, but don't turn up anything strong enough to open a door with. Except James's backpack straps. They can't come loose from the backpack and aren't that long, but are more than zero inches long.

"I don't want to mutilate your backpack--oh, I know." She unthreads both of her shoelaces and ties one end to the door handle so that a downward pull will unlatch the door, and tries opening the door while expecting the galaxy room (because that's the one she's least likely to get if it can't read her) a bunch of times from over two meters away. Hopefully she can still finesse it so that if she gets the conference room the door doesn't open far enough to be noticed by the presenter.

She gets the galaxy room reliably, it doesn't seem to have any trouble with a couple meters.

Or with the fact that she's not touching the door. It's a bit unnerving in between being the most exciting thing that has happened in her entire life.

"Okay, seriously, does everyone agree that this really looks like the work of an intelligence? I know humans think things are intelligences all the time when they're not but it reads my mind and it's attached to a doorframe and it's got minifridges in it."

Shirley nods. "It is certainly acting intelligently. And doesn't seem... seem like it works on normal physical laws."

James replied, "In short, it's magic."

Shirley grimaced. "...More or less, yes."

"Whatever it is has to be part of whatever physics reality actually runs on, but if you want to call the set of physical phenomena that can connect the same door to two places and read my intent off my neurons 'magic' I'm not gonna complain."

James says, "I read something once, some old SF with a world-hopping protagonist, that said the difference was that physics cares about what's simple in math and magic cares about what's simple in minds. I think we've established that however this works, it's the latter. At least mostly."

"That or it's doing something complicated with our minds where we can't see the metaphorical gears, but that makes sense. Anything else we want to test just the three of us? . . . I'm kind of tempted to wrap my head in aluminium foil and see if it can still detect my intent but I can't actually get a closed shell so that's mostly a joke idea."

"We should run a couple more trials for the two-opener case. And, time check on the talk, I'm less worried about someone trying to open it from inside while we have it open to the other room, but I'm not not worried.", says Shirley.

James contributes that he hasn't tried ingesting anything in the fridges, but he opened some of the alcohol to sniff it, and everything so far had its smell match the (generic, image-based) labeling. (Some of the labels weren't very informative, but he's left those closed so far.)

"Yeah I am also gonna call not-it on eating the food, we can feed some to a mouse and get it under a spectroscope and whatnot later. I'll set a timer for ten minutes before the talk ends, but that isn't going to help if someone needs to use the restroom." She sets the timer anyway. "I still want to see where the pipe in the sink goes--I bet someone at this conference knows where to get an endoscope in a hurry. What else is there . . . oh, if someone has a heat source we might be able to tell if heat diffuses through the glass over there in a way that suggests vacuum on the other side or not."

"Heat diffusion if there's vacuum... Would there be any, actually? I seem to remember space is a good insulator. From somewhere."

"Should we have someone wait inside the lecture hall? Or, hmm, not sure they could signal us if they did. Also we might need a fourth person, though I could probably bug Steve to come back out."

"Yeah, that's what I meant, if there's vacuum on the other side heat will stay in the glass longer than if there's air on both sides or a wall on the other side. But we don't know how thick the glass is so maybe that's a nonstarter. Maybe one of us should open the conference room door, count heads, then stay in the hallway without opening it again until everyone is out before opening this room again, and the people in here just keep the door shut from their perspective until the person in the hall gives them the all clear."

"Oh, right. I haven't had to work with that part of physics in..." ...Long enough that trying to count makes her feel old, which she doesn't want to admit to. "Well, in years. Also, James, we have cell phones, we can too signal each other."

James facepalms briefly. "Oh. Duh. On the other topic-" the one where he didn't just brainfart "-did the room seem like a different temperature when you first found it? It's being all suspiciously convenient for humans, for all we know the other side of the glass is in atmosphere but it's at STP... You'd think the galaxy would be hard to set up in atmosphere, but setting up two different rooms attached to the same door sounds harder, so we probably shouldn't assume."

"I didn't notice a temperature change when I first came in. Also I have no sense of scale, that galaxy could be tiny and close or huge and far away. Let me check for parallax." If she puts her head as far to the left edge of the window and then as far to the right edge of the window as she can manage, does the galaxy change perspective at all the way a small model would?"

"That points toward it being suspiciously convenient... I don't know where we go from there, though."

No parallax is visible.

"It's suspiciously a lot of things. Also it really looks like the other side of this window is actually a point in deep space, which, wow." She's not saying it was aliens but it totally might have been aliens.

"Huh, cool. I'm not quite sure if that actually makes the - implied superpowers? - of whatever created this significantly more impressive." (James was never particularly a "SPAAACE!" kid.)

Shirley suggests they should do the two-person opening trials before they hide the door and wait for the end of the talk.

(Theo has found the correct building and the hotel's internal map, and is making his way around to the location. He does not have anything marking him as allowed in the convention, but he is a young man in a nice suit, moving purposefully, and so no one has bothered him about it.)

"I dunno, I'm pretty impressed even ignoring the possibility of FTL!"

Two-person opening trials is a good idea. Ideally they should do it with two people with different "default" rooms, both aiming for their own default.

They do ten more trials of opening the door with two different aims. Four get the galaxy room, six the lecture hall, shuffled around.

"I mostly meant that I haven't wrapped my head around what the one door two rooms thing does, and that still seems like, already probably FTL and plausibly harder. FTL versus some kind of parallel universe travel is, IMO, on the same level."

"Yeah, that tracks. Man, if there's one of these there's got to be more somewhere."

Someone new has approached while they were experimenting. He is... boggling, mostly, at the door that can open two different places. But he manages to stop woolgathering, after the question. "And yet, if there are, why hasn't anyone noticed?"

"This could be the first one accessible from Earth. This could be the first one accessible from somewhere public, either as a deliberate public demo or for some other reason. It could be extremely unlikely to get the door to open to this room without knowing it was there. Actually I think that last one was just true; that only happened once in the whole talk worth of people and there could be tons of these that nobody but the creators has ever opened. Also if this wasn't a deliberate public demo whoever made it might be annoyed at having their room invaded so I'm glad we've been holding off on anything destructive."

"Have you all planned what you're going to do beyond testing opening conditions?"

"Get some more people in here with better instruments, point various sensors at the galaxy window and the closed door, check if the food is normal food and go from there."

"That makes sense. However. It is actually very important that you don't publicize this widely."

He sighs a bit.

"I am - not happy to have to squash this. Honestly, I'm pretty curious myself, I've never seen this particular kind of thing before. But I already knew supernatural phenomena existed, and there is a very good reason why those are not public knowledge. If this goes public, the body count will be... large. And it won't be people like me, who already know about it, doing the dying."

"Oh shit. What's the danger? Is it that people can hurt themselves on accident, or that it has destabilizing military applications or something?" She can kind of see how it would have destabilizing military applications and expects someone experienced in seeing things from that angle could think of more, especially if 'this kind of thing' isn't the only form that 'supernatural phenomena' can take, but she doesn't know enough international relations to say whether keeping it secret forever is the best policy.

"I'll start with the warning: Do not, under any circumstances, attempt to cast magic spells blind. My family passes down one spell, because it's the only one where the spell is less risky than the alternative. All spell development is done by senior citizens who have lived a long, fruitful life free of regrets."

"So, magic spells exist. If you have the components of a spell assembled correctly, but they don't correspond to an actual effect - and most combinations don't - you get backlash. Crippling, and fatal nine times out of ten. Fortunately for humanity, it is impossible to assemble the components correctly without a mental component which requires that you really believe it will work. And very few people actually believe that when they try to do Wiccan rituals or whatever, so very few of them die. We keep it a secret so that it will stay that way."

"That really sucks! Are you working on systematizing it so you can tell what components will work without trying? Or trying to develop computer systems capable of belief without themselves being people?" Also she really wants to know what the spell is and what it's marginally less risky than, but asking would potentially be taken the wrong way.

"We're seriously inhibited in any systematization by the thing where almost any attempt to innovate is lethal. And there are less than a hundred thousand people in the know worldwide. There are a couple variants of the one standard spell by slightly varying the gesture, but the sample size is one, goodness knows whether that would even be similar for a different base spell."

"Wait, everyone you know about only knows one working spell between them? Woah."

"Other groups I don't know well might know others. I suspect that there have been others discovered, that we forgot because they weren't that useful and teaching spells is not entirely safe.  It's possible everything else supernatural is a result of spells cast long ago, even. But we haven't done much study of it; there really aren't many of us."

"And you can't tell everyone because some of them are morons and you can't tell governments because they'd start wars and they're morons . . . there's got to be a way to get to a better state than this, though, probably by figuring out the laws it all runs on and using that to derive spells from first principles." She's possibly being very arrogant, thinking she has a hope of being able to change this situation, but it sounds like it's had a lot fewer person-hours going into it than most fields, so maybe there's some fruit an additional person could help pick.

"It's less the morons and more the people who accidentally learn just enough to be dangerous. There are plenty of ways for morons to get themselves killed already. It looks like you three have been experimenting pretty usefully on this place, which is definitely much safer and productive than the other things I'm familiar with. I really don't know why we've never found something like it before."

Shirley suggests that if they're going to try to keep the secret, they should probably discuss this inside the galaxy-box.

"Oh, yes, that would probably be wiser."

Brenda goes in as well and sets her doc of notes to private, since the guy does have a good argument and doesn't seem inclined to immediately disappear them all. Unless he's lying about not understanding how this room works and planning to disappear them all through it.

He sends a text back to Tess on the guess that he might not get signal inside, and follows.

"I think it probably doesn't do any harm to tell you the other types of supernatural I know of. The more important one is that some human deaths leave ghosts. It's very rare, maybe three or four in a million. Ghosts look like translucent humans who float a little, and drain all the heat out of a room. But they're like dumb dogs and not usually dangerous, and usually they burn themselves out quickly. But a fifth of them or so are what we call 'vampires'; they're hungrier, smarter, drain more heat, and can kill quickly. They gravitate toward population centers but there's still probably only a dozen in the five boroughs. They live till they starve, which has only been possible to do proactively in the last century, and it still is tricky."

"Do the vampires have continuity of identity and memory with their biological lives? And they drain heat? To what eventual temperature? Can they be convinced to be power plants?"

"I'm... not sure. I doubt vampires are, they're really predatory, aggressive, and undiscriminating; you don't see vampires that, I don't know, avoid children, which you'd think you would, right? I don't think we'd be able to pin one down to ask it questions, though. I've spoken with ghosts once or twice and they seemed a little bit human, but one with, like, severely impaired memory and cognition. You might be able to get a ghost to cooperate with a power plant scheme, unlikely a vampire. The trick would be getting one docile enough to just sit and 'eat'. I don't know if the temperature is consistent but it's definitely well below freezing, maybe minus 30, minus 40. And it's well above absolute zero, they can die - if that's the right word - in winter cold because there's not enough heat to drain. Not here, but if one shows up in, say, Labrador, in December, it'll die young. Dry ice barriers slow them down but do not starve them as far as I know, for that we need liquid nitrogen."

"Dry ice freezes at like minus 80, though, so doesn't that mean they can go below that? I realize that's not the main point. The main point is that it's very annoying that you can't do it on purpose and keep your brain in one piece. Do animals ever leave ghosts?"

"I'm pretty sure they don't. If they do, it must be a lot less frequent than humans. Factory farms would have seen it by now, there's, what, hundreds of millions of chickens killed a year?
I think the problem with dry ice is that it dissipates too quickly, they don't willingly go right up close to it but they can just stand a foot back and be apparently fine. I'm not a chemist, though, and I haven't gone hunting them myself."

"I had been thinking more about apes and elephants but yeah. Do you know anything about what causes them?"

"I do not. There's some superstition about violent deaths and strong emotions, but it's rare enough that I doubt that's real. We find them with magic: that's the spell I mentioned, it points out vampires within a quarter-mile or so. As far as I know it doesn't see the deaths that create them."

James is still here and is looking queasy. Shirley stayed outside.

"And a lot of the detective work that would help find out would interfere with keeping everything secret."

She sighs. It would, in some ways, be very convenient if Theodore was lying to keep all the interesting thing for himself, but her best guess is that he isn't.

"What sort of structure do you have going on, are you a corporation with NDAs or something more informal? Oh, and we should make a plan for retaining access to this room after the conference ends."

"Pretty informal, there aren't enough of us for a system. Mostly it's families who police their own. Though if this thing isn't unique... I'm not sure how well we're going to manage it."

Now that he thinks about it, sousveillance would be a problem soon, too, even without these magic doors. Crap.

"Do you know what fraction of people can get this room without knowing it's here, or whether it'll disappear if nobody's in it for a while? We could just keep it shut and, uh, sneak in at night sometimes."

"Absolutely no clue. I have not heard of supernatural doors as a thing, before today. Like I said, I'm curious. At most the cost is getting a hotel room here any day we want to check back, which is within reach if I get some help. I'm just a legal clerk but one of the junior partners is in the know and a good friend."

"I live in Boston, and this is clearly the sort of thing worth dropping out of school and moving for if necessary, but if I don't have any brilliant labor-intensive ideas by the end of the conference I would prefer a solution where I just took the train up sometimes."

"I mainly meant that a room at this hotel gives an excuse to be wandering in this part of the building whenever. Well, presumably."

"Yeah. One day at a time as we come up with ideas and to make sure it's still there, and just, keep doing what we were doing in the meantime." It really feels like discovering magic should be more disruptive than that, but honestly this is kind of crummy magic so it's not that surprising.

"That makes sense. Though, I'm thinking a bit about this and getting concerned. I happened to notice this time, but probably there are other magic doors somewhere far off and unnoticed, and if that's true, us secret-keepers are going to have to break the veil in a planned way to avoid the 'half-informed idiots committing suicide' problem. Which... well, I suspect that will be keeping me busy for a while."

"Yeah, if this happened once it can happen again, and everyone has cameras and the ability to talk to the whole world at once. Any way I can help with the reveal?"

"Investigating it while still looking like sober reasonable scientists... probably helps. I'll probably come up with something more later, we should all exchange contact information."

"...The detection spell has a variant for detecting any magic happening, which is how I saw this. And we can teach it to you, but probably I won't, I'm not a very careful teacher."

She is a sober, reasonable scientist, to the extent that humans at her own degree of rationality can be called reasonable generally, unless she's hallucinating and just got called out by her own hallucination. She takes a stab at waking up just in case; no dice. "A magic-detection spell is the sort of thing I would be tempted to overuse, so even though I really want to learn it eventually I'm not in a hurry. And yes, we should definitely exchange contact information." She sets about doing this.

"Oh, hey, what happens if someone remote-controls a robot to do a spell in another building? Does it lock onto the mental component and blow them up anyway?"

"...Huh. The mental part is the most critical, and also there are mental side effects - spells hurt, though successes don't do lasting damage - so I'd expect it to affect the person, or else not work at all. But I don't think it's been tried. Something else to test... but definitely under an NDA."

And then they investigated it, with lots of difficult legal wrangling that would be boring to read about.