Harry Potter AU where Death stops time and forces Harry and Voldemort to fix a broken timeline (Tomarry / time travel / existential horror)
This is another weird half-dream idea I had and I genuinely don’t know if it works, but I can’t stop thinking about it.
So we’re at the end of canon. Voldemort is about to kill Harry.
He succeeds.
Harry dies.
Except he doesn’t.
Instead, everything freezes.
The entire world stops moving except Harry and Voldemort.
No spells work. No movement. No sound. Just absolute stillness.
And then something else appears.
Not Dumbledore. Not magic.
Something colder.
A presence that calls itself Death.
And it basically says:
The timeline is broken.
Something happened that prevents the future from continuing normally.
So it gives them a choice:
> Fix it. Or stay trapped in this frozen moment forever.
And then it sends them back into the past.
Harry and Voldemort are forced to work together (very reluctantly) to figure out what caused reality to “fail”.
They hate each other. Constantly argue. Blame each other for everything.
- “It’s your fault for chasing immortality.”
- “It’s your fault for killing things that shouldn’t die.”
But they’re stuck together, so they start jumping through time trying to find where the timeline broke.
They end up everywhere:
- Hogwarts eras
- Dumbledore and Grindelwald’s timeline
- random historical magical incidents
- moments where things almost changed but didn’t
It becomes this chaotic, Gravity Falls-style time travel mess where they’re basically trying to debug reality.
Eventually, they discover the truth:
Harry is (or was) a Horcrux.
But something is wrong.
The Horcrux doesn’t behave like it should.
And then it hits them:
Harry stopped being a Horcrux years ago.
The moment it happened was during his 5th year.
A suicide attempt he doesn’t remember properly.
Not because it didn’t happen.
But because his mind buried it so deep it effectively erased it from his conscious memory.
And that moment is what “broke” the timeline.
Because Harry dying, even briefly, created a contradiction the universe never resolved.
So the real core of the story becomes:
They have to go back to 5th year Harry.
And stop him from doing it.
Harry has to confront a version of himself he doesn’t even remember existing.
And Voldemort has to confront the fact that the “immortal object” he built his entire system around… was unstable from the beginning.
In the end, once they fix it, time resumes.
And somehow, against all logic, they survive it.
And they don’t immediately destroy each other.
They just… exist.
Together.
Trying to pretend the universe didn’t almost delete itself.
I don’t even know what this is. It’s part time travel AU, part existential horror, part Tomarry enemies-to-something.
If anyone wants to write it, feel free, because my brain clearly doesn’t know what to do with it anymore.