Note: Also, most of the exposition would be done in the dialogues between the two main characters and the old man at the end would only wrap up odd ends.
So there are a few "chosen ones" every epoch and they are granted time warping abilities by the unknown factors of the universe. But they can not alter their own past- bad things happen i.e. lost loved ones. They are immortal in a sense, they just stop aging at around late 30ish (or any other set age), they can't interact with each other or else they age.
Plot starts out with "September 24, 1939" written on screen. Fades out to the raiding of a small eastern european village by the Germans. A young couple is trying to escape through the woods, and they hear someone behind them. Turns out to be a german soldier, who hasn't noticed them yet. Young man urges his love to run away and he'll distract them, however his wife begs him not to. However, at that moment the german soldier sees them, and points his automatic at them. The woman's lover jumps in front of him and gets shot, collapsing. He whispers to his wife to leave, as he has no hope of living. In the background, the german soldier begins reloading and yells out something to his comrades, who start to come over. In tears and in fright, the young man's wife manages to disentangle herself and begin running through the forest. However, and in her emotional instability she doesn't notice something happening to the scenery (most likely ghosting) and a whooshing sound, then she somehow appears in a village, that looks nothing like something from her time. Some image (such as a newspaper) declares the date as September 24, 2039, exactly one hundred years after the death of her husband.
Screen blanks out to black, then fades in to the main storyline.
A family is in a car, driving along but then they get in an auto accident. The mother and son go to a funeral scene with the father dead. During the next day, the kid, 11-12ish, is at school, when he gets confronted by bullies. He looks around trying to find a way out, but can't, then is slammed against a locker. He suddenly goes back in time a couple seconds to find himself against the wall, the bullies wondering how he got there. He manages to dash away, and wonders about what happened. Then he reaches up and discovers a wound on his head where he collapsed into the locker.
Kid has recently come to discover that when he sprints at a certain speed then he warps his time location, but is still confused about it. He connects this with the previous bully encounter, then he tries to go back in time when he discovers that he can do so with heavy impacts i.e trains, buses, floors, pavement, but he sustains injuries from doing so, although to a lesser extent than other normal humans. Begins experimenting with heavier falls, then jumps off a building in an attempt to prevent his father from dying. Unfortunately more carnage ensues and he loses his mother as well with a bus full of people.
The "Time Sprinters(or whatever is a good name for them) can only go back so far since the distance they travel back is dictated by the power of the impact, there is a limit to how much of an impact they can sustain. But they can sprint forward infinitely, so many end up far ahead in the future by mistake, or other means, while some continue to try to go back by finding ways to create large "impacts".
Boy is now 20ish and is in college and is abusing his time warping abilities to cheat on tests and girls and such.
Time Warpers or whatever can feel each others presence since time begins to shutter to a halt as they near each other.
Main guy through out his life notices this briefly while walking through an airport, walking through a park, at a party, at a young age when he was in middle school, and later on in high school as well, there is always an elderly man in the shadows hiding that the main character never fully encounters, but time still slows down. Main guy also encountered others briefly but they either ran away or died.
Taken from Royal Road, this narrative should be reported if found on Amazon.
Main guy encounters woman at coffee shop where he works and she tells him about who they are
they become good friends
then on morning she is gone and he looks at the television and he sees her jumping off of a huge building. Instinctively and stupidly he follows. She is angered by this.
they move back ten years or so (closer to the time of his father and now mothers death)
he then finds out she is from the year 1939 and is attempting to rejoin her fiance who was killed in WWII
He tries to convince her without avail that she cannot change her personal past, using his own past as an example, but she ignores him and continues with larger impacts, as she has nothing to lose. One of these impacts result in a car accident costing the life of a father and mother to an 8 year old.
He becomes enraged and jumps off a building and attempts to kill her in a huge, epic, climatic battle on an oil rig as she attempts to blow it up for her final impact by nuke back to 1936. During the action scene, being shot would send you back due to mini-impacts and just being too close to another Time Sprinter would cause time to stutter and slow down (bullets would stop). Eventually, the oil rig manages to explode, but they are not caught in the impact and fly outwards into the water, which absorbs most of their time-warping energy (pseudo science at work).
The main guy (now in the water) sees her unconscious drifting on a piece of driftwood. He swims over, pulls her on, and prepares to kill her in a dramatic moment.
However, the old guy (same one from the shadows) stops him the last second before he kills her (she is unconscious the whole time).
(time sprinters can kill each other)
The old guy is revealed to be a future version of main guy that has somehow aged...revelation moment...main guy is told to spare her as "harming the future does not fix the past." Old guy "runs" away but in a more ghostly manor, floats over the water and disappears. Main guy turns around to reflect on the murder he nearly committed. Scene changes to when the she now regains consciousness and looks around at all the carnage and debris. They are both now on a life raft and the main character convinces her that she cant change her past using the rhetoric of the old man.
A large ship then appears and the two are brought on-board,
-scene flashes out to the future where they both have a normal life together with children (the old guy in the shadows smiles to himself as he looks through glass door and then dissolves to dust, finally to rest in peace), kids are running around playing cops and robbers. The main guy has now aged a little and is with her.
The credits roll and it fades to going through the family photos and general household items that give a homely look, kids voices are now the main sound and then the time whooshing sound is heard and the little kids then say start saying "you were gonna run that way, I saw you" (or something similar) then piano music kicks in an the slow house tour continues to a history book in the study of the home that has a picture of the main-guy in a WWII uniform, (leaves watchers inclined to believe that they are also reincarnations of the previous warpers/sprinter/whatever).