[Estimated reading time: 13 minutes]

City lights, memories, time

The not-quite-old man stands at a cliff and overlooks the small gold rush town.
He has the city mapped out in his mind, of course, so this is just a perusing glance to figure out what has changed.
There's construction on 4th, slight change, but otherwise the small town is much the same.

He stands there and tries to imagine the high-rises that will go up in the coming decades, the housing that will eat further into the valley.
The hover car taxis will bring in visitors in droves.
The weather will be controlled.
Someday.

He looks on and ponders the mysteries of time and space from this overlook.
He pops the top on a glass bottle of Coke, sits on the hood and stares down into the growing town.
He pictures the future, the past, all the paths that lead off into an uncertain future.

The kid is out there, somewhere, somewhen.
He hasn't returned, so maybe he succeeded in his mission, maybe he did go back to the future.
The man tries to put those thoughts out of his head, but he is finding that hard to do.

It was something the kid said about the night of the dance.

The kid was on stage, serenading his dancing parents.
Then a bully cut in and pushed his father away.
Suddenly, the romance between the father and the mother was no longer a certainty.

The kid might not be born.

And this is how time responds to changes:
the kid felt like crap, his stomach hurt and every sense in his body was signalling doom, he was unable to stand, and his hand started to fade away into oblivion.

(The man thinks that the boy was experiencing two separate timelines, only he didn't exist in one of those timelines.
That might explain the strangeness.)

But then the kid's father stood up to the bully, mother and father were back on a collision course, and the kid was back.
The kid was spry and alive, once the romance between his parents was rekindled.

The man finishes off the bottle, throws it in the back seat of his car, then gets in.

"There's science to be done!" Doc says to no one in particular and drives home.

Spring cleaning, party, journal

Copernicus watches from his comfortable sleeping pad as Doc clears out his workshop.
Every contraption or device that has to do with time travel stays, everything else is being moved quickly and loudly out into the living room or even onto the lawn.
At first Copernicus is concerned about this turn of events, then he remembers that Doc is a harmless human, and promptly goes back to sleep.

Once the research is roughly sorted, Doc goes through his diaries and workbooks and picks out the time travel work he has written down so far, and puts a torch to the whole collection.
He similarly destroys his time travel inventions.
They were all based on the "flux capacitor" theory of time travel.

He burns the documents and the inventions in a small bonfire on the back porch and sits on a lawn chair and watches.
Doc gets a new journal from his workshop and draws a rough sketch of the fire.

Doc is restarting his research into time travel.
Doc might be erasing Marty's future.
He hopes to undo that, some day.

At the stroke of midnight he adds the first real entry to his time travel journal:

Hosted a time traveler party yesterday, November 26th, 1955.

Nobody showed up.

Doc repeats this every few weeks, at random, and gets no visitors.
He persists.

Doc threw out all the knowledge of time travel that was associated with the flux capacitor.
He is now starting from scratch, so to speak.

He writes down the big new discoveries and findings in his journal.
He adds in the descriptions of rudimentary time travel inventions, proofs of concept and such, they all go into the journal.
Doc finishes writing in the journal every day at 6pm.
Doc is meticulous about this.

The journal is kept in a large iron vault that Doc had paid a lot of money for, and had even added a few custom touches to it.

Weeks go by and Doc fills up two whole journals of research.
These now have a permanent home in the vault and Doc works with the third journal.

First!

On February 2nd, the clock strikes 6pm and Doc closes the vault, gives the handle a spin.

"It's a pleasure to see you, Doc Brown," a voice startles him from the center of the lab, a space that Doc had considered empty.

"My heavens, do not sneak up on a man like that!"
Doc whips around and faces a stranger in orange and yellow spandex, and little else.
"Who are you and what are you doing here?"

"My name's Eugene.
I've come from the future, from your future.
We've all been waiting...
for just this moment."

"This moment?
What on earth do you mean?"
Doc crinkles his forehead in a mock display of confusion.

"You, Doc Brown, just made a monumental discovery!
Your diary in that vault has the solution to time travel.
The people of our time wanted to visit you right at this moment, on this red letter day of science!
It's like witnessing the moon landing.
Well, you know what I mean.
I've waited my entire life to meet you!"

"Ah, my discovery!
It works!
And you are from the future.
Fascinating!"

"Yes, Doc, it works!"
Eugene is excited for this meeting, his enthusiasm is bright and nauseating.

"It's nice to meet you, Eugene.
Now, let's find out a bit more about you.
When exactly are you from?"

"2031.
I've come here from the Brown Institute, August 24th, 2031, to be exact.
It was about 9am when we started up the generators and I traveled here at exactly 9:22am.
This is, actually, our second trip."

"Wonderful, wonderful!
How are you planning on getting back?" Doc asks.
"We had some trouble last time."

Eugene' eyes get big after a moment, after he has had time to process things.
"Another time traveler?
From the future?"

"From your past.
But that was before.
What is your way back?"

"Uh, I push this button and the built-up energy..."
Eugene stops his explanation and looks at Doc with suspicion.
"You've always said that a man shouldn't know too much about his destiny.
What's changed?
Why're you so curious?"

"Curiosity comes with the territory, my young lad."
Doc smiles, but can tell that Eugene isn't buying it.
"Oh, alright, let's get this out in the open."
Doc makes a motion with his hands and the third time travel research journal appears in his hand.

Eugene stays quiet.
Doc opens the diary and takes hold of a single sheet of paper.
Doc holds the sheet and yanks away the book.

Eugene gasps, shudders, and falls to his knees.
"Damn it, Doc!"
Eugene is weak and slumps against the wall, farther away from Doc.

Doc looks down at the piece of paper, but goes to great lengths to avoid reading the findings that are on it.
The findings were great enough, Doc thinks, that they brought this traveler here, as a watcher of sorts.
The future folks know Doc's research routine, so some version of Doc has successfully convinced his successors of the importance of this moment.
Destroying this piece of paper will cut off that reality.

Eugene is writhing on the floor, his body partially transparent, his face shows unimaginable agony.
Doc drops the paper into the fireplace and Eugene disappears entirely.

Vacation, Cola, retreat

Doc takes a vacation from time travel research.
He drives an hour down the coast and spends a day on the beach, a case of Cola at his side.

The waves lap at the shore and Doc gets lost in them for a long while.

Lunchtime comes and he gets a sandwich out of the cooler, eats it and reads a paperback that someone left at the diner.

It's been a while since he fell off that blasted toilet, smacked his head, and saw the flux capacitor.
The imagery is burned into Doc's eyes forever.
But not its impact.
Doc is studiously excluding any research or findings based on the vision of that day.

It's taken me nearly thirty years and my entire family fortune to realize the vision of that day. My God, has it been that long?

Doc remembers watching his future self, one that no longer exists, the one who followed with utter conviction his vision from that fateful day.

Doc drinks the Cola, watches the ocean, and ponders the big questions:

• Who implanted the flux capacitor in my head?
• Has it always been there?
• Why did it bewitch me so?

Doc stays a week at a retreat on the coast and comes away with four journals of writing.

Continuing research

Doc comes back to the time travel research and picks up where he left off in the diary.
A few shreds of paper remind him of the missing page, but he pushes on.

Doc splits up the specific research that drew the time traveler here, and schedules it for two separate weeks.
One half will be done one week, the other half will be finished the next week.

The research from the first week goes into the vault, but no time travelers show up.
And none are around for the customary time traveler party.

So Doc goes through with the second set of experiments.
These, he posits, will yield the results that caused the time travel breakthrough.
At least, they did last time, in 2031.

Old books

Doc's family came to this town with few possessions, they mainly brought books with them.
The love of books is central to his being, in some sense.
The library of this house has been expanded twice already, and Doc wonders if there's space enough left for both his laboratory and the library.
But that's a decision that can wait.

Doc dedicates every Thursday to systematically going through each and every book in the library.
It is something he has done before, gone skimming through every book, but he has not done this in the past four decades.
It's been a few weeks and Doc has only gone through about a quarter of the books, but he continues, picks up every Thursday from where he was a week back.

On Thursdays, Copernicus finds himself a comfortable chair or couch, one that is within sight of Doc, and zonks out, typically listening to the classical records that Doc is so found of.

Finally, Doc has something to show Copernicus!
Doc is blabbering on and on, of course, but he is also holding up one of those strange book things that the master is so fond of.

The books are strange, and their insides are dangerous.
The few times that Copernicus was able to get close enough to the inside, he was always shooed away.
The strangeness had tired the poor dog, so now he prefers to watch the insides of the books from far away.

Yet Doc keeps coming back with the inside, practically shoving it into Copernicus' face.
The inside is just paper, Copernicus remembers, and suddenly the inside kind of makes sense.

Copernicus sniffs at the book's inside, notices its musty smell, understands that it is probably moldy as well, likely has spent quite a bit of time locked away.
Then he remembers the paper, looks at it and rotates his head around, this way and that, his ears flopping.

Copernicus jumps off the couch and bounds for the garage.
Doc follows behind, smiling.
Copernicus runs up a ramp and onto a work table, then sniffs at a piece of paper and looks up at Doc.

The piece of paper has Doc's drawing of the flux capacitor on it, the three shaded pieces converging into a donut-like center.

The book that Doc holds in his hands has the same diagram.

Second

The second set of time travelers appear just as suddenly as the first, again after the pivotal bits of research are locked up, and Doc pretends surprise yet again.

This is a duo of warriors, both women, encased in heavy and obviously used battle armor, its surface is scoured with blast marks.
Doc wonders if they've just come from a war.

"Welcome to 1956," Doc beams at the newcomers.

"Thank you, Doctor Brown.
It seems we are expected?"

"I had no doubts that someone would visit me, but had no idea it would be the two of you.
Who are you?"

The two women introduce themselves as Astrid (half her hair is shaved off) and Nadia (terrifying eyes) of Brown Institute, 4th Airborne.
They explain that the Allegiance has just acquired the time machine plans.

"Oh, well, we can't allow that injustice to stand.
Can you tell me what year you come from?
Do you know a Eugene?"

"2029.
How did you-"
Astrid is astounded and terrified at Doc's words and the journal that appears out of thin air.
(Doc has been spending quite a bit of time practicing sleight of hand.)

Doc manages to quickly burn the page with the results, but Nadia is very close to him and almost kills Doc, her heavy fist misses its target by mere inches.
The duo fade into oblivion and Doc wonders not for the last time about how bad of an idea all of this is.

Time Leak

The concept of the Time Leak, as Doc explains it to Copernicus, is simple:
Doc presents theories and waits for time travelers to show up and confirm those theories.

Consider the case of Marty.
Doc arrives, by "pure chance", on the Flux Capacitor theory of time travel.
Some 30 years later that theory manifests as a time-traveling DeLorean and shows up on Doc's doorstep, mere hours after Doc comes up with the theory.

If Doc's theory was wrong, Marty wouldn't have been able to go back in time.

Consider the case of Eugene.
Doc arrives at the Valence Cloud theory of time travel and records it in his diary.
75 years later, the Valence Cloud theory finally leads to successful time travel, so Eugene comes to Doc, mere seconds after the key elements of the theory are locked up in the vault.

Doc burns his research, notes that he would need to continue in that exact vein, and in so doing Doc unmakes Eugene's reality.
Someone in the future apparently convinces the scientists of the prestigious Brown Institute the importance of visiting Doc at these pivotal moments of time.
That someone is likely himself, Doc explains to Copernicus.

This is how Doc figures out a way to get information from the future, by controlling the existence and nature of time travel.
The Time Leak.

Further research

The design of the battle suits gives Doc an idea, so he adds a few energy research topics to his study syllabus.
Doc uses the Time Leak to test out other theories.
They have to be related to time travel, of course, or otherwise he'd have no way of verifying them.

The next time traveler is from 2028 and shows up with an electric suit of armor, so Doc learns that his latest theories about energy generation are accurate.
The traveler fades away as Doc's research burns.

Ancestry

Doc's family came to the States from Germany in 1908, and at the time they were the Von Brauns.

The book with the Flux Capacitor diagram is a German book of mathematic riddles and tricky problems.
The diagram is a puzzle about train routes in Germany.

Then Doc finds a second book of riddles, and it too contains the flux capacitor diagram.
This time, it is a puzzle about capacitors, but it uses the same image.

In his childhood, Doc had worked through six of the German puzzles books in his family's library, as much as he could read and understand.
These two "flux capacitor" puzzles seemed normal enough at the time, Doc recalls, so he saw nothing special in them, just solved the tricky setup as he always did.

The book must have come from Germany with the family, all the way across the ocean.
The books of puzzles date to late 19th century and were largely submission-driven, with local nerds sending in fun little trifles to stump other local nerds.
Both of the flux capacitor puzzles were sent in by a Mr Ziegler from the small town German town of Druze, in the County of Schaumburg.

Eugene

Eugene comes from 2024.
He appears in the middle of the lab, a cloud-wrapped statue of glistening gold.
His suit of armor is the result of yet another theory research project into the weak nuclear force.

"Doc Brown!
Congratulations!"
Eugene shouts.

Doc looks up from the vault, appraises the fine craftsmanship of the suit, then rips out a page of research and throws it into the roaring fireplace.

The golden god fades into nothing in less than a breath.

Travelers, prototypes, experiment

Over the course of a few months, Doc is visited by travelers from 2024 (again), 2021, 2003, 1991, 1980, 1962, and 1961.
(Only one of them is Eugene.)

It is late 1956 and Doc has many working prototypes of unheard-of technology.

He kisses Copernicus on the head and says his good-byes.

He looks around and a tears well up in his eyes.
But Doc pushes through it.

A large, bulky harness hangs from the ceiling of the lab.
Doc steps underneath it, the harness lowers, he wriggles inside and straps himself in.

He puts on a dark brown duster and a matching hat.
In his hand is a sleek bone-colored weapon, which he holsters for the moment.

There is a single red button on the front of the harness.
Around it, though, is a copper ring.
Doc rotates the ring then hits the button and from his point of view the universe

shifts

and he is now standing on a gravel lot under a full moon.
It's 3am, the year is 1902, and Doc is in Hanover, Germany.

Hanover, Druzel, Gustav

The field is a development lot and is close to a major road.
Doc has no problems just walking into town.
He gets a coffee at the diner and pays with a familial heirloom, a rare coin that his grandfather had given to Doc's father.
It somehow feels appropriate.

From Hanover, Doc takes a bus to the neighboring town of Druzel, then walks into the industrial area of Druzel.
He eventually finds and walks to a large warehouse.
Sparks somewhere inside strike surfaces and illuminate the whole interior a pale shade of blue.

Doc approaches an ajar barn door and peeks inside.
He sees a young man in black protective gear at an antique workbench working with a generator.

"Gustav Ziegler?" Doc asks the young man.

"Yes, that's me," the man responds in German.
"What do you need?
How can I help?"

"I was curious...", Doc replies slowly, his German is very rusty, "about these puzzles," Doc holds up one of the brand new puzzle books that he picked up in the Hanover train station.

"Ah.
He said that someone might come asking about that book."

A wave of energy slams into Doc and blows away large chunks of the duster.

Reply

Doc turns, the bone-colored weapon spits out an impossible elongated bullet, and the shooter is pinned down, skewered simultaneously through his midsection, his weapon, and the brick wall.

Parts of the attacker shimmer and disappear for a second or two.
It is a cover or invisible suit of some kind, but they're of course malfunctioning, so the individual cells flicker on and off.

Doc watches this for a moment and ponders the technological marvel.

The attacker has a metal mask with red eyes and a vertical grill for a mouth.
It shudders in pain.

"What in tarnation are you?" Doc asks the pinned attacker.

"What in tarnation are you?", the attacker replies in a rusty groan of death.
He punches a few buttons on his wrist computer.
"Your world, dies!", the attacker exclaims.

The wrist computer shows a sequence of red lights, and they slowly turn off, one by one.

"Tarnation," Doc says.

The end

The nuclear blast tears off the rest of the duster, but Doc's personal force field holds.

Doc sighs, rotates the dial on the front of his harness, slams the button, and the warehouse

shifts

and is back, undestroyed once again.
It is now one minute ago.

Doc is already turned toward the invisible attacker.
The bone-colored weapons spits out a bright-orange sphere the size of a watermelon, a mashup of thick, bright waves travels along its surface.
The sphere encounters an invisible barrier and expands in shape to cover the target.

The attacker's invisibility cloak flickers on and off before finally disengaging completely.
The attacker is frozen, the orange outline around it is still.

"What are you?!" the German man exclaims after a moment.

"It is complicated," Doc sighs.
"I come from the future.
Do you understand?"
Doc wonders for a moment if he learned the wrong German phrases.

"Yes!
That killer, that predator, it explained what it wanted.
It crashed its air carriage in the woods, many decades ago.
My father saw the trails in the sky one night...
It was trying to make time travel..."
The young man searches for the right words.
"It wanted to use time travel.
It forced me to leave clues, for the future people."

Doc nods, "I understand.
It waited for a time traveler to come asking questions.
I used the same approach.
That is how I built this suit."

Gustav looks over at the strange orange statue in the corner of the warehouse.
"It planned something terrible.
What will you do with it now?"

Doc takes a 1956 camera out of his duster and starts taking pictures of the trapped alien.
"It may have friends.
We're going to send them a message."