Disclaimer: J.K. Rowling owns Harry Potter.

Hey there! This is my first fanfiction story so I apologise in advance for any errors/mistakes. I have been planning this story for a while and intend to complete it, but I will only do this if I get enough people reading it, so please review or follow! I will ignore any flamers but constructive criticism is welcomed. If you have any questions about this story then just send me a PM or comment in the reviews.

Summary: What if on that Halloween night at Godric's Hollow, Sirius had an even bigger reason not to go after Peter? What if Harry and his brother in all but blood, Leo Black, were raised marauder-style by Sirius and Remus? As dangers threaten to tear apart his world, Harry and his friends must train together in order to take down the most feared wizard of all time, Lord Voldemort. Features a smarter, more confident Harry, who will do anything to protect his family and friends. No bashing! Harry/Hermione

The sky was getting darker as the evening drew on and silence fell over Godric's Hollow. The children had long since returned from their trick-or-treating and families slowly began to draw the curtains and settle down for a well deserved night's sleep. Only one house was still awake.

Harry James Potter had been unable to sleep and was being comforted in his mother. Lily held him securely in her arms, humming softly to him. Her husband, James, was sat down opposite, a copy of the Daily Prophet in his hands. His face was grim as he scanned over the front cover.

"Anything I should know?" asked Lily, taking in his expression.

James handed her the paper. A muggle family in Devon had been found dead in their home, the Dark Mark cast above the house.

Lily shook her head sadly. "It's horrible. People are dying everywhere and it's like we can't do anything about it."

James reached over and squeezed her hand. Harry watched with wide eyes as he reassured her. He had no idea that this would be the last time he would see his parents so close to him, the last time he would hear their voices filled with so much love and affection for each other. James grinned as he saw Harry's adorable green eyes staring up at him. He knew he would never be able to put into words the love that filled up in him as he gazed at his little baby son and vowed that he would do everything in his power to give Harry the good life he deserved.

Lily seemed to understand what he was thinking because she planted a soft kiss on Harry's forehead, stroking his soft tufts of black hair, and said, "He'll be a wonderful man when he's grown up, I know it."

They sat in silence for a while, until Harry finally drifted off to sleep and Lily returned him to his cot.

James was on his way to fetch Harry's blanket when he heard the sound of the gate swinging shut outside. He frowned. Nobody was supposed to be calling by tonight, and certainly not at such a late hour. He walked over to the front door, only to see it blown off its hinges and clatter loudly to the ground beside him. His puzzled expression turned to one of fear and shock when he saw the dark figure stood in front of him.

It was him.

Voldemort.

James reached for his wand only to realize that it wasn't on him. Lily stumbled out of Harry's room to see what had caused all the noise. James waved frantically for her to back off.

"Lily, take Harry and go! It's him! Go! Run! I'll hold him off –"

Lord Voldemort let out a cackle of high-pitched laughter. "Those are brave words, James Potter, but there isn't much you can do without a wand. Go now and flee. Let me kill the boy."

"Never!" shouted James.

Voldemort's face twisted into a malicious smile. "That's a shame… AVADA KEDAVRA!"

There was a flash of green from Voldemort's wand and James fell to the ground. His body lay there, motionless and cold, and Lily let out a cry of horror.

"Such an unnecessary death…" Voldemort said softly. "I only want to kill the boy. Give me Harry Potter and I won't need to kill you too."

"Not Harry, not Harry, please not Harry!" cried Lily.

"Stand aside you silly girl … stand aside now."

"Not Harry, please no, take me, kill me instead –"

"I said stand aside!"

Lily shook her head, tears streaming down her face. "Not Harry! Please… have mercy… have mercy…"

There was another flash of green light and Lily crumpled to the floor in front of Harry's crib. Harry sat there silently, not understanding what was going on but scared of the horrible man looming over him. Voldemort gave a cold, cruel laugh and raised his wand on Harry.

"AVADA KEDAVRA!" For the third time that evening the same green flash lit up the room, but this time something was different. Harry felt a burning pain in his forehead and blacked out, a small trickle of blood leaking out of the scar that now marked his forehead. Voldemort knew something was wrong. He was in agony. He felt as though everything inside of him was being set on fire. With one last cry of pain and horror, Voldemort fled.

Tonks House, 31st October 1981

Sirius Black was sat with his cousin Andromeda and her husband Ted Tonks in the kitchen. He felt as though something was wrong, but he didn't know what it was. He was supposed to be checking up on Peter soon to make sure he was ok. Whilst he was confident in his decision to change the secret keeper, he worried for Peter's safety. he knew that if something happened to Peter, he would never forgive himself.

Originally, Sirius had planned with James and Lily to become their secret keeper himself, but he had thought it better to give the role to Wormtail whilst still spreading out the rumour that it was him. This way Voldemort's followers could torture and kill him, but the secret would still be safe with Peter, whom nobody would suspect.

Sirius ran his fingers through his hair, sighing. The past couple of years had been very stressful for him. Not only were Voldemort and his followers causing chaos and terror, but his former immature, care-free self had been forced to grow up fast with the increasing responsibilities that had been heaped on him.

His brother Regulus had visited him just under two years ago, apologising for the many mistakes he had made in his past. He had informed Sirius that he had something important that he needed to do and had begged him to look after his pregnant girlfriend, Kyla Zabini, in the event that he was killed. Sirius agreed and three days later, Regulus was declared dead. From then on, Sirius had done his best to protect and support Kyla, whom he soon became very fond of.

Like himself and Regulus, Kyla was born into a pure-blooded family. Despite not being supporters of Voldemort, her parents still had strong views about muggles and muggleborns, which Kyla disagreed with. Instead of attending Hogwarts, Kyla had been home-schooled by her mother. She met Regulus at the beginning of his seventh year and they fell in love almost immediately. Regulus had been forced to keep their relationship quiet as he knew his family would disapprove, despite her being pure-blooded. Even once she became pregnant with their son, he didn't tell his parents.

It was mid-September when Kyla was due to give birth. Sirius was told that there had been some problems and had spent the entire night at St. Mungo's, pacing nervously up and down the length of the waiting room. The Healers assured him that everything would be fine, but despite everything they did, Kyla died minutes after the baby was born. He still remembered her words to him as she lay there dying, her newly born son held in her arms.

"Look after him for me, Sirius. Promise me you'll look after him."

"Of course I will," croaked Sirius.

"What would you like to call him?" Healer Clark asked softly.

"Leo," Kyla whispered. "Leo Regulus Black."

Kyla's death affected Sirius a lot. He felt himself becoming overwhelmed by sadness, guilt, and the responsibility of raising a baby boy on his own. Only he wasn't alone. James and Lily, who were expecting a baby of their own and his cousin Andromeda, who already had a small child, provided the support he needed and he began to regain control of his life. He loved Leo like he would his own son, and when little Harry was born, Sirius felt as though he was complete again. Despite the guilt he felt for being unable to look after Kyla as Regulus had wished, he instead vowed that he would make it up to them by always being there for Leo.

Andromeda broke him away from his thoughts as she got up from the table to check on Nymphadora (Sirius still couldn't believe she had called her that), who had, to Sirius's amusement, a habit of sleep-walking. Only a few days ago, Andromeda and Ted had woken up to find that their daughter had wandered into the laundry closet whilst sleeping and woken up lying on a pile of dirty washing. Sirius thought it was hilarious but had earned a glare and a whack on the head by his cousin after he said this, so he had wisely decided to refrain from giving his opinion on the matter in the future.

"It's still a little early, but I'll go check on Peter now," said Sirius, getting up from the table as well. "Are you sure Leo will alright staying here?"

Ted nodded. "Just do whatever you have to do. Leo will be fine with us."

Sirius landed his motorcycle outside Peter's house shortly after and knocked on the door. There was no reply. Sirius frowned. He knocked again but with the same result. Scowling, he pulled out his wand and muttered, "Alohomora." The door unlocked and Sirius pushed it open.

As he walked inside the house, Sirius noticed it was empty. This was strange – there was no reason why Peter shouldn't be at home. In fact, he had assured Sirius that he would be there. Now certain that something was wrong, Sirius quickly retreated to his motorbike and left towards Godric's Hollow.

The moment Sirius touched down on the ground, he sprinted towards the house. He ran straight past where the front door should have been and sank to the ground in horror as he saw James's body. He desperately shook his best friend's body, pleading for James to not be dead, but he knew it was pointless. As he got back to his feet, the truth sank in. James had been killed. Avada Kedavra by the looks of it. And Sirius knew that Voldemort had been here.

"It was Peter…" muttered Sirius. "Peter betrayed them."

Sirius took a few deep breaths and carried on walking towards Harry's room. When he saw Lily crumpled on the ground, he couldn't stand it any longer.

"DAMN YOU PETER!" he roared, anger and betrayal pulsing through him. He had trusted Peter! And Peter had sold James and Lily to Voldemort.

When he looked up, he saw Harry lying in his cot.

"Please don't be dead, Harry, please don't be dead," whispered Sirius.

He picked up Harry and was relieved to find that he was alive. Unconscious, by the looks of it, but alive. A strange mark was on his forehead; Sirius realised it was the shape of lightning.

"Don't worry, Little Prongs," said Sirius. "I'm going to look after you."

As Sirius wrapped Harry tightly in a blanket and held his securely in his arms, he heard voices coming from outside. Quickly, he left the house through the back and climbed onto his motorbike. Part of him wanted to go straight after Peter, to hunt him down and kill him for what he had done, but he knew that both Harry and Leo needed him. Wormtail would have to wait.

With that final thought still fresh in his mind, Sirius took off into the air.

So, the first chapter is complete! I hope you liked it. If you want me to carry on writing this story then please give me a review. Hopefully, the next chapter will be up in a week or so.

If you have any questions about the story then please tell me in the reviews and I will do my best to answer them.