The Butterfly Effect.

Chapter 1.

The evening was surprisingly cold for early August. Although it was only eight o'clock the light was already beginning to fade. The moon was muscling its way in, attempting to take the sky from the sun, if only for several hours before it would be forced back again.

The moment Sirius Black had arrived home for the summer holidays his room had been dismantled. Red drapes from the walls now lay strewn across the floor, the emerald green paint that lay underneath finally allowed to breathe. The canvas portraits of The Noble and Most Ancient House of Black that he had hidden in drawers, buried under various items of clothing, were now dotted around the room. He had thrown them in anger at the walls and left them where they had fallen, destined, it seemed, to spend an eternity staring at the ceiling. Finally pictures of what he had once thought of as his real family had been plastered across the room, dumped on every surface, so there was always one visible from every angle. Most of the pictures were moved on a daily basis, from place to place, as a pale hand grabbed them, their crumpling edges retreating more each day. He would check at intervals, whether James Potter, Remus Lupin or Peter Pettigrew had returned or whether the portrait still contained just the one member, himself, staring dejectedly at the floor. Shameful tears sometimes escaped the portraits eyes.

The real Sirius lay flat out on the only space of floor left. It was cold hard wood, rough from the wear and tear of being crushed by agitated feet for hundreds of years. But Sirius relished the discomfort, he understood now that pain was something he deserved. One of the pictures was clutched in his hand, currently residing at his side. He lifted it up painfully slowly so he could see the picture, every ounce of his being wishing that he could just catch a glimpse of one of his friend's faces. It wasn't that he needed to see them, he could see them alright, their images floating around his head, disapproval clear in their eyes. He just wanted them to be thinking about him, he didn't like to think that he had just been cast out and completely forgotten. Nothing. Just himself. Tear stained and distraught. Stuck in a nightmare, alone forever. He shook his head, returning his hand to his side and tightening his fist around the picture, forcing more creases into the paper. He took in a deep breath of the dusty air around him and let it out slowly through his mouth, it was the only control his had now, his life was off-kilter, hurtling out of control. He couldn't even control the tears, protect his dignity, as they rolled mercilessly down his pale face that hadn't seen the light of the sun in weeks.

Yet he knew he did not deserve dignity either, so he did not struggle as the tears began again. The force of gravity pulled them down to the floor, so they trickled uncomfortably into his ears. The memories flooded back, another wave of tears joined them. The horrible moment that would haunt him for the rest of his existence, one sentence that he hadn't even thought about at the time. It had ruined his entire future.

The boys greasy hair stuck to his face as he turned, "I know you're up to something Black," Snape snarled, "You, the half-blood, the blood traitor and the coward."

Sirius chose to ignore the insults, now was not the time to land himself in detention Moony needed him, "We're always up to something," he chuckled.

"You know what I mean, something beyond the school, something bigger..."Snape stared unblinkingly at Sirius, his mouth set into a determined line, "I will find out Black."

Sirius let out a bark of a laugh, "You want to know what we're doing?" Sirius's eyes sparkled dangerously, "Go to the Whomping Willow tonight, the knob on the at the bottom freezes the branches, there's a secret tunnel underneath. You'll get what you deserve, Snivellus."

Sirius briefly saw Snape looking suspicious as he turned, but he knew that curiosity would overcome his distrust. A grin spread across Sirius's face, it was not until later that he was forced to face the consequences of his actions.

...

"SNAPE COULD HAVE BEEN KILLED! I COULD'VE BEEN KILLED AND DID YOU EVEN THINK ABOUT WHAT IT WOULD HAVE DONE TO REMUS?" James yelled, "Don't you even care? Didn't you even think?"

Sirius sat quietly on the bed in the dormitory, taking his punishment.

"Well?" James demanded, his eyes wild, "Answer me Black!"

Sirius visibly flinched, James knew he hated the name but ignored the hurt that appeared in his best friends eyes.

Sirius jumped up from the bed to respond, his survival instinct from years of insults at home kicking in, "I'm sorry!" He said, his voice forceful but not quite a shout, he was trying to restrain himself, he knew he was in the wrong, "I've told you countless times, and Peter, and Remus, especially Remus," he faltered, "I'm such an idiot, and don't I know it. I'm so sorry!"

"Sorry isn't good enough Black," James answered him quietly, his voice still harsh.

"Prongs, please..."

James eyes flashed and Sirius fell silent. James walked up to Sirius, so their noses were centimetres apart, staring him straight in the eye, breathing heavily. Even though Sirius had a slight height advantage James's stony expression still chilled Sirius to the bone.

"Don't ever call me that again! Do you hear me Black? You're just like them, we were the idiots, thinking that a Black could be different. Leave the marauders alone, traitor."

James turned quickly and left the room so that Sirius wouldn't see the tears that were filling up his eyes at a rate of knots.

For the final two months of term not one of them had said a word to him. Either they walked away if they were somewhere around school when he attempted to approach them or pretended he wasn't even there and stayed talking amongst themselves. He began to sleep by the blazing fire in the common room, every night waiting for it to be vacated before he could curl up on his favourite armchair in peace.

He had once ran into Peter, the two of them alone, a rare occurrence. As Sirius had begged with Wormtail, the watery-eyed boy had stuttered, mumbled and retreated. Typical Peter.

But James words still echoed around his head, bouncing around in the emptiness their absence had left behind,'...You're just like them...Black...leave the marauders alone...traitor...traitor...traitor...'

"Sirius!" A sharp voice snapped his name between her vocal chords, shaking him from his reverie, "Dinner!"

Sirius groaned as he got up, stretching out his back like a cat, a strange comparison for the animagus, and made his way downstairs, each step leading to another evening of questioning and insults.

XXXX

Sirius picked up his silver cutlery apprehensively, beginning to pick at his chicken with his head down, apparently intensely interested in cutting it correctly.

"I had a terrible day at work today," His father, Orion Black, drawled, "Too much trouble over a group of muggleborns going missing. If you ask me..."

"Lovely chicken," Sirius interrupted, he couldn't bear to hear how his father was going to end that sentence.

Orion smiled sardonically, "I'm sure kreacher has done it in the same way as he always does," Walburga frowned at her sons praise of the house elf before returning to her own meal, surprisingly without comment, "We haven't been getting much post lately." He said it as if it didn't matter, but his smirk showed that it meant more than would meet the untrained eye.

Sirius groaned inwardly, of course his parents would have noticed when they screened the post that nothing was arriving for him from his friends. Not that it ever got to him anyway, it was always hidden, or sometimes even burnt.

"I was hoping that you'd come to understand the truth of the matter," Walburga began, a smile gracing her aged face.

At this opportune moment Regulus decided it was time for him to explain the situation to his parents, reminding them he was there. Regulus craved his parents attention, but they were too busy trying to get Sirius back in line. They weren't the sort of parents who did praise, they were more accustomed to giving out punishment.

"He hadn't been with them much at school very much lately. There were rumours..."

"Regulus!" Sirius hissed, "Don't talk about things you don't understand."

"People were saying that Sirius had, changed his loyalties, that he was a traitor to the Gryffindors."

Sirius leapt up from the table suddenly, catching it and rattling the things that lay on it, "I am not a traitor!" he roared the sentence, trying to convince himself as much as everyone else.

"Sirius sit down!" Walburga snapped. Her son stayed on his feet, reaching one hand into his pocket, checking for his wand, something that always made him feel safer, "Sit down." She repeated sternly.

Sirius sat slowly, not taking his eyes off his brother, fixing him with a glare.

Strangely enough Orion was smiling, "A traitor to your family and a traitor to your friends. What will we do with you."

Sirius repeated himself in a strangled voice, trying to ignore James's voice in his head, "I am not a traitor!"

'Traitor...traitor...traitor...'

"Sirius now you've got past this silly phase we can get you back on track," Walburga sounded horribly delighted.

'Traitor...traitor...traitor...'

"We might even be able to convince Dumbledore to let you move houses," Orion suggested, Walburga nodded vigorously.

The two were oblivious to Sirius, who was slowly shaking his head from side to side. He wanted to dispel James's voice, it wasn't working.

'Traitor...traitor...traitor...'

"I don't want to move houses!" Sirius insisted, snapping his head back to stare at his parents again. He had one small triumph, "They won't let you anyway."

'Traitor...traitor...traitor...'

"Don't be awkward Sirius," Orion demanded, "If that's the case may be we could move you to Durmstrang."

'Traitor...traitor...traitor...'

A horrible thought suddenly entered his head. Would the others even care if he moved houses, or schools? Surely not, it would make it easier for them. He gulped but his thoughts turned to Dumbledore, he wouldn't, couldn't, let them do this. The sorting hat finalised it, right?

Regulus smiled broadly at his brothers distress as Kreacher began to clear up the plates. Regulus stared straight at Sirius, his lips forming the word as he heard James repeat them over and over in his head.

'Traitor...traitor...traitor...traitor...traitor...traitor... traitor...traitor...traitor...traitor...traitor…'

"Stop it!" Sirius shouted jumping up again, everyone turned to look at him, "I'm going upstairs."

"Sirius Orion Black," Walburga said firmly, ignoring Sirius's wince at his full name, "Sit down this instant."

"I can't, I've got to go..." Sirius muttered.

'You're just like them...'

"Sit down."

"No I..."

'Leave the marauders alone, traitor...'

"Sit down!"

'Traitor...'

"No..."

"SIT DOWN!"

Walburga had got to her feet, her face flushed a rosy pink. Her wand was clutched in her right hand, pointed straight at Sirius's face. "Sit down," she repeated, her voice shaking as much as her hand.

Sirius hesitated, his eyes searched his mothers face warily, "No."

"Sit down," Her voice was still eerily calm, "Or I'll make you."

Sirius briefly wondered how dinner had come to this but, out of stubbornness more than anything, remained on his feet.

"IMPERIO!"

The curse took Sirius by surprise, partly because she shouted it so loudly, and partly because it was the first time, out of so many threats, that she had actually turned her wand on him and used an Unforgivable Curse. He stunned look dropped from his face as she forced his to sit down on the seat.

It was an odd feeling being under the imperious curse. It was as if he were suspended in an immensely dense liquid, unable to move or protest. Sirius thought it must be like being entirely paralysed, when other people move your limbs for you and there is nothing you can do about it.

He tried to struggle against it, but it was as if he had lost every muscle in his body, he felt weakened by it.

She finally lifted the curse and he began to gulp in oxygen even though his breathing had been totally fine for the entire experience. He stood up again, slowly because he now felt extremely unbalanced and stared at his mother in disbelief.

She just stared back at him, no remorse shown on her face, eyes emotionless, "Why are you standing up again?"

He hesitated again, taking in another deep breath before continuing, "I'm sick of this, of you. I'm going upstairs."

He tried to stay calm as he sprinted from the room and took the creaking wooden stairs two at a time. But the thought crept into his mind, he couldn't keep it at bay. His own mother had used an Unforgivable Curse on him, he couldn't stay, he had to get out of Grimmauld Place before they seriously hurt him.

He dashed into his room and began flinging things into his school trunk. How long did he have? Could he even make it to the door with the heavy thing? With that thought he grabbed a handful of the money he had saved up and dumped it into his pocket.

"Son, come here now," Orion was outside, his voice quiet but dangerous.

Sirius went to the door, dragging his trunk behind him and came out onto the landing. His father stood a few meters away, wand out but by his side, a grim smile on his face. Walburga, however, still had her wand out and at the ready in front of her. Regulus watched from behind, his earlier smirk had gone from his face, he hadn't expected his mother to go so far. Kreacher stood on the stairs, trying to look impassive but failing to keep the smile from his own face.

"Those blood traitors and half-bloods are nothing, you are a pure blood Sirius, there is no need to mix with them any..."

"Them?" Rage filled Sirius along with another batch of tears. Deep anger built within him and quashed all rational thought and he began to shout, "That blood traitor and half-bloods were my friends, the very best. Don't you even care that I was happy?"

"You can't be happy with them!" Orion roared.

"Hogwarts with them is the only time I've ever been happy!" Sirius's shout echoed through the house and was followed by a deafening silence. His parents stared him down.

"We have done everything for you!" Walburga screeched.

"You've just pushed all your ideas onto me! I can't breathe in this pure blood obsessed family..!"

"Crucio!"

Once again Sirius had a millisecond to be surprised by the use of a second Unforgivable Curse in one night. Then a crippling pain seized his entire body, every muscle, every cell tightened in agony. He lifted up onto the tips of his toes while his body doubled over and he tried not to let out a sound. Blood pounded in his ears, his chest tightened and he couldn't breathe. Suddenly the pain was gone, but the relief he had expected did not come, his muscles could not relax so quickly after such intense pain. It was a slow recovery until his body was pain free again. His heart and breathing rates had sped to over twice their normal speed.

"I can't stay here," He grabbed his trunk and started to drag it, ignoring his arms protests.

"You're not going anywhere," Orion snarled.

"I'm leaving," Sirius hoped his voice sounded stronger than he felt. The idea hadn't really sunk in yet, he just needed to get out.

Ok, hope you liked that. It was a surprisingly long chapter for me but I am going to try and keep them that way. Please leave a review and thanks for reading.