A/N: First of all, let me thank all of you who reviewed, pmed and mailed me with your kind wishes and support. It means a lot to me, and to my husband. People say the internet is impersonal, but it really, really isn't. Even if I don't know your names and you don't know mine, you really help me cope. A thousand thanks for that!

I've been writing a bit these past weeks, because I honestly don't know how not to write, and it's turning out okay, I think, so I thought I would share it with you. This story is more adventure than angst and has a lot of humour in it, even though it touches on darker topics, too. I hope you like it, and I also hope you understand that I can't promise regular updates on this one, life being what it is, so I can very well understand if you decide to wait until it's finished (Those of you who have no idea what I'm on about, go check the last chapter of "Had I Known".

A few preliminaries: The story takes into account canon until the Weasley-wedding at the beginning of Book Seven, including Horcruxes and Deathly Hallows, and will share general plot points with the whole of "Deathly Hallows". It begins one and a half years after said wedding, with most of the Order dead and Harry, Hermione, Neville and Luna searching for Horcruxes on their own. Basically, things went pear-shaped somewhere along the way, and they're coping the best they can. You will learn more about the Alternate dimension in the course of the story…

Enjoy! – Oh, and I disclaim! I disclaim most thoroughly.

Chapter 1

Deep in the bowels of Gringotts, Harry Potter and Hermione Granger were fighting a dragon.

Things were not going very well, but that was so much of the ordinary these days that it had them barely worried. Too busy to worry, actually.

While Hermione was hard pressed to keep up a shield against the dragon's fire, Harry Potter, leader of the rather pitiable opposition against Voldemort, was being defeated by a lock.

A medieval lock, to be precise, but it was goblin made and hellishly stubborn.

"I can't hold it much longer," Hermione yelled, her shield charm flickering under the onslaught of flames.

"Nothing's working," he yelled back. "You wanna try?"

She nodded, and when the stupid – and huge – dragon next drew breath, they changed positions with the ease of long practice.

Not that it helped any.

She hit the lock with every spell Flitwick, Bill Weasley and the Hogwarts library had ever taught her. The metal burned with spellfire, but the Lestrange-vault remained secure. Damn goblins!

Harry's shield was still holding, but even he couldn't keep this up forever, and she could hear the battle sounds drawing closer. Luna and Neville were quite the team, and in the narrow tunnels two people could fight a larger group to a stand still, but only for a time.

"You have to use fiendfyre!" Hermione screamed.

She could barely hear her own voice over the dragon's roaring, but Harry understood.

"We don't know what's in that vault!" He shouted back. "We could start a magical chain reaction…"

We could also be killed by a dragon! Very soon, in fact!"

Harry hesitated. Hermione knew he was considering their alternatives and coming up with nothing at all. She saw his face harden and knew he agreed with her.

"Position change… now!" She shouted and once more raised the shield while Harry let his spell fall.

It was harder this time, and she felt the force of the dragon's attack in every bone. They couldn't keep it up much longer. At least Neville and Luna were still alive, and coming closer by the minute from the sounds of it…

Then she felt the atmosphere change, her own magic screaming in the air, and knew Harry was wielding fiendfyre.

The dragon ceased his attack – perhaps even he was shocked by their daring -, Harry shouted in triumph, the vault door crashed open, something exploded…

…and Hermione was drowning in magic.

Meanwhile, in a world very much the same and yet fundamentally apart, two friends sat talking within the strong walls of Hogwarts, warmed by a merry fire and the flow of their conversation. It was old custom for them to sit together like this, the familiarity of the situation connecting the schoolboys of once to the grown men of the now.

The clock roused them from their talk, and though neither of them felt the slightest inclination to brave the Scottish winter in the middle of the night, duty was duty, and even a Slytherin could not always shirk it.

"It's your fault," Severus Snape accused his second oldest friend while donning a thick black cloak and a green scarf. "I wanted to take autumn duty, but no, you were too busy chasing after that woman and so we have to trudge through this damn blizzard instead of getting drunk."

His companion grinned, white teeth flashing in a face that was considered 'dreamy' by the majority of the female Hogwarts population.

"Jealous, Snappy?" He asked.

"Don't call me that," Severus said, but the demand lacked conviction. This exchange was as old as their friendship, and even stubborn Severus had given up on ever losing his childhood soubriquet.

"Oh, but you love it, I know you do…"

"Shut up, Fluffy, or I'll sic Lily on you," Severus sighed, doused the candles and aimed a slight stinging hex at his friend to get him moving.

Who simply swatted it away, expecting nothing less from his Severus after all these years.

"You're getting slow," he teased. "I think the life of quiet research and scientific achievements doesn't suit you."

Severus just laughed. "You mean compared to living with hundreds of students in a damp old castle? No, thanks very much. If there was one thing that would surely reduce me to a miserable old bastard, it's teaching."

"Teaching's lovely," his friend disagreed while they traversed silent corridors and headed out into the glittering cold of Scotland in December. "You just have to keep them interested, is all."

"And how are you doing that?" Severus drawled. "By flashing your smile at the girls and your auror badge at the boys? Demanding work, I must say."

This time, the hex was aimed at Severus, but he blocked it with the same ease before turning his attention to their task. There had been no threats to the castle as of late, and their wards were holding stronger than ever, but even the finely spun net of Hogwarts' protections had weaknesses, and one of them was the border to the Forbidden Forest.

So no matter that they were at the oldest magical institution of Europe, with one of the most powerful wizards at its head, patrolling it was. Even in a blizzard.

Severus sighed. Then he dutifully performed the location and detection charms that were a part of the job and spent the time they were running on a clever plan how to somehow get snow into his friend's collar. Ah, the simple joys of school.

But the results of the spells sent these thoughts right out of his head.

"Two intruders," he whispered, his eyes already straining against the darkness. "They should be somewhere to the left. Can you…"

"On it. Give me a moment."

Severus slowly followed, a shield spell waiting for activation at the tip of his wand. He wasn't a bad dueller, but he lacked his friend's experience, and he would be damned if they caught him unaware. But nothing happened.

"Oi, Severus, over here!"

No nickname, no joke. Severus hastened his steps until they stood once more side by side.

He was looking down at the unconscious bodies of a young man and a girl, both no older than twenty. They lay close to each other, limbs thrown haphazardly across each other, faces caked with grime and blood, and yet they looked strangely peaceful. There was no sign of how they'd gotten here, no hint of another intruder, and Severus' hasty spells confirmed that. He crouched down, slipped their wands from their hands and secured them in his pocket, and then allowed himself time for closer observation.

They were dressed completely wrong for the season, he next noticed. Though both were wearing what looked like an assortment of torn shirts and sweaters, one layer over the other, the girl's right arm was bare except for a wandholster, and the boy's cargo trousers were of a thin material more fitting for the summer. Also, their hair was singed. Quite badly.

And the boy had the sword of Gryffindor, the mythical weapon kept safe by Dumbledore's phoenix himself, strapped securely to his hip.

"Huh," Severus said, glad that only his friend could witness the expression on his face.

And Sirius Black, Head of Slytherin House, veteran Professor of Defence Against the Dark Arts and partner-in-crime of Severus Snape, met his best friend's eyes with echoing shock, their easy banter forgotten in the face of this mystery.

A/N: The next chapter will have a very uncooperative Hermione and a lot of discussion about the colour of Snape's robes.

Review, please!