AN: I started this book shortly after reading "Order of the Phoenix" so some information from later books may no longer apply, but several chapters at the end are more up to date. This portion of the fic is completely finished and I plan on continuing through to more books after. Let me know what you think. Oh, and I changed the story slightly so that Regulus is two years older than Sirius, though he won't come in 'till later in the fic. Sorry, some of these chapters will be short and there will most likely be a lot of cliff hangers (they are so much fun to write and I couldn't think how to end the chapters except with one)

Part One

Harry Potter sat on his bed. It was about five weeks since he returned to Number 4 Private Drive from Hogwarts. The summer had never seemed so endless.

After his third year he had always hopeful of Sirius coming to take him away so he could live with him. But that was no longer an option. After what happened in the Department of Mysteries, it seemed that he would only be able to leave after his graduation from Hogwarts after his seventh year. That left two years.

"Oh, Sirius, I should have listened to you and the others when I was told to stay put. I should have left Snape to his own business and continued with the Occlumency lessons. I wish there was some way that I could go back and change everything from where it went wrong. My parents and you would be alive and everyone would be happier." As a tear made its way down Harry's cheek and he slipped into sleep, he didn't notice that he had been staring at the first star of the evening or that it flashed brightly for a moment.

Nineteen years in the past

James, Remus and Sirius were hanging out in James's room. There was nothing to do because it was raining outside and since Lord Voldemort was on the rise to power, none of their parents would allow them to be far away from an adult. Well, at least Remus's and James's parents wouldn't, Sirius's couldn't care less.

"Come on, you guys," James said, "We're the Marauderss we should be able to think of something to do."

As he said this, there was a loud pop and something fell from the air above James's dresser and landed on the floor. As Remus, who was the closest, went to pick it up, a bright light flashed for a moment and then was gone.

"What is it?" James asked.

"It's a book," Remus replied as he studied it.

"Well, bring it over to the bed. We don't have anything else to do so we might as well read what it says," said Sirius.

"Wow," said James, "I never thought I'd see the day when Sirius would suggest we read something."

"Yeah, well I'm bored," said Sirius.

Seeing a fight coming and hoping to forestall it, Remus said,"It's called Harry Potter and the Prisoner of Azkaban. Hey, James, do you have a relative named Harry?"

"Not that I know of," said James.

"Well, let's read it and find out. I'll go first," said Remus. He opened the book and on the first page he noticed some writing. "Hey, there's something written here, a kind of prologue."

"What does it say," James asked.

"It says, Beware those that read this. For what is concealed in these pages will shake a lifetime of friendships. All I ask is that you read the book from beginning to end before jumping to any conclusions. Remember that an alter ego reflects the characteristics of all forms. Remember that this is not just a book and that the information enclosed can not only save a life but bring down a traitor and the one he works for. Well, that doesn't make much sense," Remus said.

"Maybe, it will make more sense as we go along," said James.

Sirius said nothing. A certain suspicion was mounting in his mind about a certain absent marauder. For some time, he had noticed that Peter seemed to be keeping more to himself. In fact, he seemed more like his animagus form, his alter ego if you will, than ever before. The phrase from the book rang through his head. 'Remember that an alter ego reflects the characteristics of all forms.' Did Peter really have all the characteristics of the rat form? He shook his head, he was probably reading too much into the changes in his friend. Little did he know that his suspicions would grow as they read the book.