Disclaimer: I in no way, shape, form, spirit or hex own the rights to any Harry Potter character. But then as readers of this you should know that.

Summary: Two years after Voldemort's defeat, lives are left in shambles. A younger friend of Harry's decides to go back in time to help her friends.

A/N: Okay. It's a time travel story. And yes I am aware that these are everywhere. But I wrote this for fun and to deal with my total obsession with Sirius and the rest of the Marauders. I love this time period, and wish more was done with it... but anyway... If you like it (or even if you don't) leave me a review. It's always nice to think people care... flutter

Chapter One:

As she snuck down the hall to Filch's office, Serena had to keep reminding herself that what she was about to do was for the good of her friends. Everything she was doing was to help save them from the misery that had always been present in their lives. And since she cared about them so much she was willing to risk the happiness of the rest of the world.

In her seventh year at Hogwarts, Serena was a member of Gryffindor. It was something she took immense pride in. She loved her house, and for her there was nothing greater to be proud of. After all Gryffindor had been the house of Harry Potter. And Harry Potter had been the one to finally rid the world of Lord Voldemort.

He had also become a friend of her's in his last year at the school. That had been only two years ago, while Serena, had been an, as till then, unknown member of Gryffindor. Somehow in her fifth year, with everything happening around them, Serena had managed to become close friends with Harry, and with him the rest of his gang including Hermione, the entire Weasley clan, even Harry's girlfriend Ginny. She had become their friend, and then in that last year watched as it all went wrong.

Yes, in the end Harry managed to finally defeat Voldemort, ridding the world of that scourge. But at what price was their happiness paid? It left Harry with no one to turn to... His parents were dead, his godfather was dead, his mentor Dumbledore was dead, and in that last battle he lost everyone else that was important. Sure they weren't all dead... but some were as good as, if not wishing they were dead. Ron had died, and due to that sad fact, Hermione had since shut herself off from the rest of her friends. Lupin was killed as well, by Peter... though Lupin managed to bring down his once friend with him. Tonks was as inconsolable about this, and became like Hermione, no one had seen her since. The Weasley family itself never really had managed to get over Ron's loss, and wasn't the same place since. There wasn't laughter and joy anymore...

And the result of this all was, that Harry had completely blamed himself for the unhappiness surrounding him. After all with no Voldemort anymore, who was there left to blame? Everyone should have been happy it was all over, but how could they when so little was left. And Harry felt he should have done better protecting everyone. Who could have told him otherwise? With Sirius, Dumbledore, Lupin, Ron and Hermione all gone no one he trusted could set him straight. Ginny tried, she really did, but all Harry saw when he looked at her was her dead brother, and the unhappiness living in her family.

He sunk into a deeper pit of depression.

Serena wanted to help him. She, like most of the others that had survived, felt guilty. Why had we survived? For what purpose? She didn't doubt that Dumbledore would have been angry with all of them giving up, forgetting the love that still existed. But as much as she wanted to give comfort to her friend, it was hopeless. She had been a friend... but not a very close one. That didn't stop her though from wishing, and plotting a way to change this all.

And the answer had come the summer before her seventh year at Hogwarts. It was going to be the first year that none of her old friends would be there with her, since Ginny had graduated last year. The summer had seen her reminiscing over her life at Hogwarts, thumbing through old photo albums. She paused at a picture she had taken of Buckbeak, or Witherwings if you preferred, on the school grounds and her mind immediately brought up the story Hermione had once told her.

"Harry and I once saved Sirius from the dementors. And Buckbeak. It was amazing... We used the time turner to go back through the day..."

Hermione's voice faded out in her brain, and Serena's brain focused on only one part of their conversation.

The Time Turner...

If it could go back a day... why then couldn't it go back a year? Or two? Or even 20?

And that was why Serena found herself hidden under Harry's invisibility cloak. She felt a slight twinge of guilt, seeing as how she had stolen it from Harry... but she justified it with the fact that she was using it to make him happy. Now she was using it, and the map she had also stolen from Harry, to get to Filch's office without being found out. All to steal a time turner, that she knew Filch had confiscated.

"I solemnly swear that I am up to no good." Serena whispered, tapping the map with her wand. Harry had once told her proudly about this map, taking great joy that his father and godfather had created it, and that it would show every passage and every person in the castle. Thanks needed to be sent to the creators, since it was certainly helping Serena that night. Without it she wouldn't have been able to duck out of Filch's way as he dove out of his office, the words "Peeves" and "eviscerate" hanging in the air as he passed.

Serena quickly made good use of the distraction and slipped into Filch's office, which was overflowing with all the things he had confiscated from students over his long career at the school. She noticed with a grimace the ever growing list that covered an entire wall of his office. It listed all the things that were not allowed. The last she had heard it had reached 1,500 offenses. She spared a moment to wonder how many of those offenses had been created by the Weasleys, or the Marauders back in the day. But the reason she was there called her back, and she quickly used a charm to bring the time turner to her..

"Accio Time turner." Immediately a necklace flew into her hand, it was a dial that when turned would send her forward or backward in time. She took care though not to mess with it at that point though, and slipping the invisibility cloak over her again, she left Filch's office.

Once back in the Gryffindor common room, she relaxed, sitting on the coach and going over her plan in her head.

She was going to go back 20 years, back to the age of the Marauders. It was all very simple. At least in her head it was. She was going to save James and Lily. The only way she could think of to do that was to make sure that they did not choose Peter Pettigrew as their secret keeper. Instead the honour had to go to either Sirius Black or Remus Lupin. That would mean breaking up the inseperable Marauders, and she would just be an outsider, who none of them knew. But it was worth it... so it was worth trying.

The only snag that she needed to get over was explaining her presence at Hogwarts. After all she was going to be a seventh year, when no one had ever met her. The only conceivable way to get around this was to go to the only person she knew would be there that could help her.

Albus Dumbledore.

Of course there was no way she could tell him the exact reason she was there. Without ever having known him that well, she knew completely that he would frown on her changing the future. Even to save lives... even to possibly save his. So instead she would tell him a slightly true lie. That she had accidentally used a time turner and that she had since lost it... She wouldn't have, but she couldn't risk him sending her straight back. And since they didn't exist 20 years ago, she didn't have to worry about that.

Serena took a deep breath, the cloak and marauders map safely tucked in her belt. They would be the only two things she needed to bring with her. Taking another deep breath, she turned the time turner until she was 20 years back in the past. Not that looking around her at the Gryffindor common room could tell her that. It had changed surprisingly little in the long years, her only indication of the year, was the calendar hung on the wall, showing what she supposed was a Quidditch team waving.

Standing up, she quickly tucked the time turner in a pocket of her skirt, and flew out of the common room, only to find herself running past the Gryffindors returning after the year's sorting.

"Did she just come out of our common room?"

"I haven't seen her before..."

She left them all gossiping behind her. She would have preferred to have arrived a bit before this, but she had to see Dumbledore immediately to explain her presence, before having any tricky conversations with people about why she was there.

"Sticky Fizzlewhits" She announced rather hopefully to the phoenix statue. She had already stood there for a few minutes, saying every single candy she could think of, so she was thrilled when it finally opened at allowed her entrance to Dumbledore's office. She knocked quite quietly, since now she was starting to feel the nerves of what she was doing, and where she was. A commanding, but soft voice, though told her to enter, and she without thinking did so.

"I don't know who you are." Dumbledore said suddenly and without preamble. He was watching her quite calmly though, regarding her already dressed in Gryffindor colours.

"Professor!" Serena cried and flew forward into his arms, surprising herself at how easily the fake tears sprung to her eyes. After all she needed to convince him this was an accident, so doing so meant some acting on her part. "I'm sorry! I'm from 20 years in the future! I accidentally used a time turner and it sent me back all this time. I don't know anyone and I miss my friends! But I can't go back since I somehow lost the time turner! You're the only one I knew would be in this time still, even though you have no memory of me! I don't know what to do!" Serena sniffled rather pitifully, and wondered whether her own tears were fake or not.

Dumbledore though was trying to console the poor girl, patting her hair, and without a second believed her completely. At his immediate faith in her, she felt a little sick on the inside, but reminded herself that this was for everyone's good.

"It's okay my dear... We'll find some way to send you back home, though I fear it can't be tonight We don't have time turners in this age, even though there are prototypes."

Serena couldn't hide the widening of her eyes, though she quickly hid it by wiping her eyes. It had never occurred to her that there might have been prototypes, she had just gone by the date of invention in a book she had read. Dumbledore seemed to misread her widened eyes.

"Don't worry my dear. There is no way I would let you use a prototype, no matter how much you want to return home. We'll find some other way. Until then though you're welcome to stay at the school. You don't have to attend classes if you don't want to..."

"No.. It's okay professor. I can't just sit down, I'll just go to class like normal." Serena sniffed pitifully again, and paused to wonder if she was going a bit overboard with the pity factor. But Dumbledore just smiled calmly. While it was certainly true that she didn't like to sit around and do nothing, the real reason for going to classes was to be around the Marauders.

"Well then my dear, we'll just let you stay in Gryffindor, since that appears to have been where you have always been. As for an explanation of who you are... We'll just say you come from Beauxbatons."

"Um, sir..." Serena piped up quietly. "I'm not french, how am I going to explain going to a French school?"

"Simple enough, just tell them you're British but since your parents moved to France for work, you had no other choice. Most people never lose their original language."

"I suppose that would be believable... I've read enough about the school to pass off going there, and I think I know enough French to pass off having lived there. I'll just say I'm abysmal at languages when people tell me I'm terrible at French." She laughed softly, tears gone from her eyes.

"Good, glad to see you've cheered up." He regarded her calmly. "Go see Professor McGonagall and she shall take you to the common room and introduce you. I'll see to books and clothing to hold you over during your stay. Good night."

Serena didn't doubt that this was a dismissal, and turned to leave.

"And don't forget. Tell no one anything of where you come from."

Serena turned and stared at Dumbledore, not doubting for an instance that he was talking about where she lived, but what time, and in that simple sentence she also knew he was warning her from telling anything she knew of the future.

"Yes Professor. Good night." She left the room, and hurried down to McGonagall's office, receiving a mild shock. She knew McGonagall had been there a long time, but it was surprising to see her so young, only in her early thirties, and amazingly so she didn't have her hair pulled back into its severe bun. After a quick explanation, leaving out time travel, McGonagall nodded and led Serena back to the Gryffindor Common room, and the younger girl had to pretend that she knew nothing of where she was going.

Entering the common room, even at the late hour, they found five people still awake, lounging lazily on the couch and chairs. Serena swallowed hard, since looking at every single one of these people, she knew exactly who they were. She knew their names, their futures, and even worse she knew how each one died...