It looked like rush hour in the Tokyo subway, but less organized and without white-gloved guards to push people.

It looked like Black Friday at Macy's, but without the murderous stares and the foaming drool.

It looked like a modern Woodstock, but with K-Pop and J-music instead of teeth-played guitar riffs.

It looked like a visit of the pope in South America, but with gods called Toriyama, Abrams or Jobs.

It looked like ... a hell of a crowd!

It was 8.30 on a Saturday morning. The clouds were low and dark-grey, but the place—an ugly exhibition center lost in an ugly Parisian suburb—was packed. From the subway's exit on the central square to the main gate, a packed and colorful crowd was waiting for the convention to start.

Rajesh Shepard (he had chosen his alias himself) had forgotten the exact name of it, but it mentioned Paris (because twenty miles outside the actual city limits was obviously still close enough), and there was a pun with either comics, manga, sci-fi or games.

The atmosphere was easy-going and friendly: cheap Klingons chatting with low-cost X-men; sleazy Narutos laughing with transgender Harley Quinns; three feet tall, genuine-looking Optimus Primes hitting on slutty, scantily-clad whatever characters... Rajesh hated all of it. Maybe because he himself was only surrounded by acne-ridden, insecure teenagers.

Suddenly, a stampede. The sixth since he'd arrived. Like before, there were outraged screams, some laughter, probably some "accidental" butt grabbing and the calm restored itself. Rajesh was fed up and started to consider dropping the mission. But this time, something changed. A few feet away, a decent enough Gimli appeared above the crowd, probably standing on a platform or someone else's shoulders. His voiced boomed as soon as something close to silence fell on the square together with a few raindrops.

"Ladies, gentlemen and other unsavory characters, please hold and be patient a few moments more. The doors will open anon!"

Whispers ran through the mob. The human-sized dwarf sighed.

"The doors will open soon," he said, disappointment tainting his voice.

But when cheers exploded, it brought a smile amid his impressive, braided ginger beard. Considering the dedication of some to their characters, Rajesh was still not sure the remarkable ginger bush was fake.

He had chosen comfort over cosplay for himself. He was wearing blue jeans, sneakers, and a shirt that could have fit the event if the zombie on it hadn't been the Iron Maiden one. Suddenly, Rajesh felt out of place: he was older than most here, his hair was obviously too short and too salty and he couldn't remember if Naruto was a pirate or a ninja.

Before he could definitely ruin all chance of blending in by asking one of the moody teenagers around him, a joyful clamor erupted from the crowd. The doors had been opened!

Anon indeed, thought Rajesh.

People hurried inside the gigantic halls to queue some more behind desks and almost famous authors, actors, artists - whatevers. Ten minutes later, Rajesh was inside and standing in front of a colorful map made out of pink squares, white alleys and blue numbers. The brouhaha was already unbearable. The sooner he was out, the better.

There! Conference room 21B! Not too far away...

And quiet! Rajesh sat with a sigh of relief. He had chosen the last row on the right, close to the door. He was not the first in the room, but it had been a close call. Three other guys were already waiting for the conference to start.

Rajesh checked the brochure for the hundredth time. It was more like a small flyer with blurry pictures of a DeLaurean and an English Police booth, a vague recap of the topic, directions and, at the very top, a tacky title in ugly font:

Time Travel in Fiction

Lies, Traps and Impossibilities

Rajesh chuckled as a nerdy, handsy couple took their seats.

Fifteen minutes later, an impressive population of twenty souls was scattered in the vast conference room, when a man hopped on the little platform and stood behind the wooden reading desk.

Rajesh shifted in his chair impatiently. He had come from very far to see this conference, sent by his boss to evaluate the man currently trying to organize his notes and clearing his throat all too ostensibly. He looked like an university teacher with his crown of brown hair, his untamed beard and his corduroy jacket. And yes, even leather elbow patches... Not afraid of clichés, are we?

Silence fell on the room and Marcus Delaunier started to talk.

"Have you ever seen Terminator 2?"

No one answered, of course.

"If not, you may have picked the wrong convention. Please leave the room quietly, then leave the building, the country and, if you can, the planet!"

Behind Delaunier a picture appeared on the screen.

A low, polite laughter came from somewhere in the room. Rajesh rolled his eyes.

"Now, for the others, please try to remember the reason given for the rise of the machines, Skynet, the war and the whole movie franchise: Cyberdyne Systems--a big company running its computer with MS Dos or Windows 3--finds itself in possession of a Terminator hand.

"With this hand and the microchip in it, Cyberdyne will create Skynet and therefore, the Terminators.

"But wait... If Cyberdyne create Skynet from the remains of a Terminator, where does the hand come from in the first place?

"From a future that doesn't exist yet! A future that can't exist!

"This paradox is only one example among the plethora found in fiction. An example that leads me to make a sad but necessary statement: authors should stop writing about time travel!"

Some spectators started to show signs of loud disagreement, throwing names like Zemeckis, Orwell or even Donnie Brasco. Delaunier just smiled and waited for the calm to be restored.

"I know, I know, there are pretty good pieces of work out there! But even if they are very entertaining, most of them, if not all, are as impossible as the Terminator franchise.

"It's what I'll try to explain in the coming hour. We won't have time to evoke all the scientific theories like faster than light travel--and I have to admit I'm not qualified enough to do so, even with the help of Wikipedia--but let's start with some unbreakable rules:.

"Rules number one: for each cause, there are consequences!

"I know it sounds obvious but it's very important. Any action, any choice, even if seemingly insignificant, may have dreadful consequences. Or at least, unexpected ones.

"Let me take an example: One morning I decide to shave. My wife is thrilled to feel my baby skin again and she throws herself at me. I'm late for work. I'm fired!"

"What if you don't shave?" called a man from the audience.

"Fair enough, I don't shave. My wife tells me I'm not doing any effort and leaves the house pouting. I'm on time at work, but when I come home, my wife has left, taking the dog with her!"

This time, people really laughed, to Delaunier's visible content.

"Rule number two," he went on. "As per rule number one, every modification in the past changes the future.

"This seems logical right? But apparently it's something most of the authors forget about when writing about time travel. Or worse, they perfectly know it, but they discard it with the cheap and easy trick called 'paradox'.

"Remember my Terminator example? Let's try something else now. Let's say I go back in time, for a very good reason like killing Hitler when he was just a failed painter or invest in Google before the year 2000. In the process, hopefully by accident, I kill my father--or mother, let's not be sexist--before I was born. So if one of my parent died before I was ever born, I can't have been living to go back in time and kill them. So they live. So I can go back in time and kill them. So... See? Paradox! Breach in the space-time continuum! Implosion of the Universe! Destruction of the reality fabric!"

Someone called out from the audience, "That's not a Paradox, that's the 2016 US elections!"

People laughed, Rajesh smiled, Delaunier seemed annoyed that his dramatic effect had been ruined. When people returned their attention to him, he pouted a few second more before resuming his presentation.

"Rule number three: going back to the future is a bit more complicated than finding fuel for your DeLaurean.

"Congratulations! You went back in time and you got rid of Hitler! You change History, saved billions and probably allowed human race to wait for a few years before starting a second world war. But now you're in 1920's Germany and you want to go home. Well bummer! You're kinda stuck!

"Changing mankind history, you also made sure that your present ceased to exist. You have nowhere to go home to!"

In front of Rajesh, a man stood. "I'm sorry sir, but you just said that changing the past could lead to paradoxes and world destruction. Is killing Hitler not a cause for any time-traveler not to be born and... and... etc...?"

Delaunier showed a wide and scary grin, "Exactly! I see that at least one of you is following! Before going on deeper into that explanation, let me add that for the same reason a time traveler can't go back to where he came from, traveling toward the future is also impossible! Don't take me for a 1970's English punk, but there is no future, only a myriad of possibilities in perpetual change!"

Apparently, there was more than one person to follow:

"But what if there is a destiny?" someone asked. "Wouldn't that mean that, as everything is predetermined, time travel is possible? In both directions?"

Delaunier stared at the woman, remaining silent for a while, then smiled and answered, "Sure! But if everything is written, if nothing can't be changed, what would be the point of time travel?"

Rajesh had had enough. This Marcus Delaunier posed obviously no threat to the Company. And never would. He sighed, both in relief to see an end to this ridiculous mission and in annoyance to have lost so much time. He stood up and, careless about the current topic discussed by Delaunier, he cut him short.

"Great Scott! This is such a pile of horse shit!"

He left the room, slamming the door to emphasize his dramatic exit. He found his way to the nearest bathroom. There was a five yards queue for the women's, as always, but no one in the men's. Rajesh didn't wait for it to change. He took the precious little device from his pocket, aimed at the nearest wall and zoom! opened a portal. He looked at the smooth iridescent surface with a satisfied smile.

It was time to leave the past and its clueless charlatans. Time to go home!