Warnings: slash, the G-rated kind.
Disclaimer: Of course, I don't own the Harry Potter universe or anything in it.
A/N: This was my answer to a challenge for the Severus Sighs group.

Chapter 1: Everything at Once

"The only reason for time is so that everything doesn't happen at once." - Albert Einstein

Severus Snape was stalking the corridors, searching for students breaking curfew, when it happened. There was nothing to warn him that his life was about to change; no footsteps to signal an impending arrival. From nowhere, a body crashed into him, sending them both to the floor with enough impact to drive the breath from their bodies.

Severus racked his brains, but no matter how much he pondered it, he still could not fathom how he had ended up beneath this man. There had been no one in the hall with him. Apparition inside Hogwarts was impossible, so where had he come from? The man muttered an apology as he began to disentangle their limbs. The professor righted himself gracefully while the other man clambered clumsily to his feet.

"Severus?"

Severus frowned, not quite able to place him, even though he seemed familiar. Obviously he was not a student; the man looked to be about his own age, if not a few years older. He knew every other professor on staff, of course, and this man wasn't one of them. He supposed Albus might've had a visitor.

"Do I know you?"

An undecipherable expression crossed the man's face as he wordlessly answered; lifting the hair off his forehead to reveal a faded scar in the shape of a lightening bolt. It was Severus' turn to be completely stunned.

"Potter?! But you're... you can't be..."

Never had the potions master been so inarticulate. Harry laughed at the unusually flustered potions master, until Snape pointed his wand at him. Harry raised his hands, palms up, in the universal symbol of peace.

"Severus, I can explain - "

"No. You are not Harry Potter. He is a student here. I don't know who you are or what you hope to gain by this deception, but you will not succeed."

Severus' voice was the low, hissing threat that made students cry and grown men flinch. Harry just sighed. Explaining his situation was going to be nearly impossible. Especially since the only man who could help him, still hated him in this time.

"Severus, listen. I can explain. I suggest we go to your lab and you can give me veritaserum. Will that convince you?"

Potter's offer was a good indication that he was telling the truth. Severus was intrigued. How and why would an older version of Harry Potter be dropping in on him? Literally. And why the devil was the over-grown brat calling him by his first name?

"It's Professor Snape to you, Potter. I accept your proposal."

With that he turned, robes billowing, and headed to the dungeons, not looking behind him to see if his unexpected visitor was following.

Harry stood in place for a moment, smiling fondly at the memories that last statement evoked. Shaking his head in amusement, he trotted after his future husband, hoping this would be the time they found a cure for his random time-shifting so he could get home to his Severus.


TBC...