Disclaimer: All characters and plot belong to J.K. Rowling. Some lines are taken directly from Harry Potter and the Prisoner of Azkaban and are also the property of J.K. Rowling.

Author's Note: Really, this all started from me wondering why Lupin was on the Hogwarts Express, and then being kicked off the computer and TV by a thunderstorm after watching PoA. I don't know if this will be continued or not, but for now it's just a one-shot. Oh, and I have no beta so all mistakes are mine.

Professor Remus Lupin,

It has come to my attention, and I am sure to yours as well, that the start of term is two days after the full moon. Seeing as you wish to remain at your house until the start of term and because of the full moon being so draining on you, you can take the Hogwarts Express to the school at 10 a.m. on September 1. This should ensure that you find a seat before most of the students arrive.

Sincerely,

Albus Dumbledore

A weary smile crossed Lupin's face as he made his way through King's Cross Station, a suitcase and trunk in his hands. Dumbledore was an amazingly thoughtful man. Remus had been planning to apparate into Hogwarts around midday, despite the full moon being only days before.

Usually he would be recovered enough from his transformation by then to apparate from his home in the London suburbs to the Hogwarts Gates. Now, however, he was very grateful for accepting Dumbledore's offer for the use of the Hogwarts Express. His transformation two nights prior had been exceedingly painful and left him more drained and weary than usual. He doubted that he would have had the strength to apparate to the Hogwarts Gates without a fairly long rest along the way.

Remus stopped and looked up at the barrier between platforms 9 and 10. There was the solid looking wall separating the muggle and wizarding worlds. He calmly strode towards it, being jostled this way and that by muggles, remembering how, the first time, he had feared that his condition wouldn't allow him entrance. And later, how he used to look forward to entering Platform 9¾, knowing that James, Sirius, and Peter would all be there waiting for him on the other side. Now he was the only real Marauder left…

Then he was through the barrier, facing a red steam engine, with the same shimmering steal plating and elegant gold lettering that he remembered from childhood. The Hogwarts Express. The most looked forward to train ride in most wizarding children's minds. A ride he had never expected to take, not after being bitten…

Remus shook his head slightly to clear his mind and headed toward the train. He nodded to a conductor as he boarded and then headed past many empty compartments on his way to the back. He didn't exactly want to advertise himself being there since, as an unwritten rule, teachers almost never rode on the Hogwarts Express. Besides, James, Sirius, Peter, and he had usually ridden in the back of the train.

He entered one of the last compartments and levitated his trunk up into the luggage rack, the tag with ProfessorR. J. Lupin hand written on it facing front.

Now there's a sight I never thought I'd ever see, thought Lupin, chuckling slightly to himself. What would James think, me teaching his son Defense Against the Dark Arts? Fairly ironic that most people think that I'm a dark creature, yet I'm teaching defense.

He made his way to one of the cramped bathrooms to change out of his muggle clothes and into his familiar, patched wizards' robes. Once he returned to his compartment, he sat down heavily in a window seat, conjuring a bottle of whiskey and a small cup. He drank only a glass or two when his eyes began to burn from exhaustion and his body pleaded for rest. He was still worn out from transforming.

He wrapped himself in his cloak, resting his head on the cool window. He shifted, moving his cloak to cover his face from most of the cabin to block out some of the light. He could now hear a few families out on the platform, though his window didn't face them. He'd just rest for a few moments, he promised himself. Just a few moments…

He was cold. Too cold. He opened his eyes, seeing only dim shapes moving in the misty darkness out side the train window. He heard voices near him in the compartment.

"Come on in and sit down."

"Not here! I'm here!"

"Ouch!"

"Quiet!" said Remus softly in a voice rough even to his own ears. He had been warned by Dumbledore about the new guards around Hogwarts and the cold, clammy air stood only as proof to their presence. He sat up, conjuring blue flames into the palm of his left hand. At least he wasn't too drained for that bit of wandless magic. His eyes darted quickly around, somewhat thankful for the enhanced senses given to him by the recent full moon.

"Stay where you are," he said, his voice still soft. He could feel the dememtor drawing nearer. He stood slowly, cautiously, feeling his muscles ache in protest. He took a step toward the door when the creature outside opened it on its own. He felt a cold rush of air as the dementor took a breath. The ache in his muscles increased as memories of his many transformations flooded him.

A boy in front of him fell out of his seat. Harry Potter. He looked so much like James that he couldn't be anyone else. Despite this knowledge, Remus simply stepped over the boy, drawing out his wand with his flame-free hand.

"None of us is hiding Sirius Black under our cloaks," said Remus, holding both his voice and his wand steady. He filled his voice with authority, though he doubted he had any over this dark creature. The dementor didn't move. "Go!"

"The dementor still didn't move. He was beginning to feel its effect on him more than ever now. He raised his wand, pointing it right at the dementor.

"Expecto patronum," he muttered, remembering the day that, despite his condition, he had received the letter from Hogwarts. A silver wolf shot out of his wand, lunging at the dementor, which immediately fled. He looked down the corridor outside, but there was no sign of any dementors and lights were flickering on, slowly stretching towards their compartment.

Turning back to the children, he glanced at all of them. Sitting in the seats to his right was a round faced boy and a girl with medium length red hair. On the floor, kneeling next to the unconscious black haired boy he assumed was Harry, was a lanky boy with the same red hair as the girl in the seat. Next to him knelt a bushy haired girl who was slapping Harry in an effort to wake him up. All of them were quite pale.

Remus walked over to the seats recently vacated by those on the floor and sat down, leaning forward with his arms on his knees to get a better look at Harry's condition. He was about to reach for his wand to revive the boy magically when he awoke on his own.

Remus saw a sheet of sweat on the boy's face as he looked around the compartment . As Harry's eyes briefly met his, all doubt about his identity vanished. It wasn't just the lightning bolt scar on his forehead that gave it away, but his eyes. They most definitely identical to Lily's green ones.

Remus broke out of his reverie to reach into his robes for a bar of chocolate, half listening to the students' conversation about Harry hearing a woman screaming. He had his own ideas about what it was, but he wasn't going to voice it. He broke up the chocolate bar, giving Harry the first and largest piece.

"Eat it," he said quietly, his keen, blue eyes surveying the boy. "It will help."

"What was that thing?" asked Harry. Lupin could hear a slight unsteadiness in his voice. He should make sure that the boy was checked over once he got to Hogwarts.

"A dementor," he said, still breaking up pieces of chocolate and handing it to the students. "One of the dementors of Azkaban."

He rolled the empty chocolate wrapper into a ball and put it into his pocket, ignoring the fact that they were all staring at him. He glanced at all of the students, smiling slightly when he saw that none of them had eaten any of the chocolate.

"Eat. It really will help," he said again. He stood up, glancing around at all of them.

"I need to speak to the driver, excuse me." He walked out of the cramped compartment and down the hall toward the engine.

He spoke briefly with the conductor standing in front, who promised to send an owl telling either Professor McGonagall or Madam Pomfrey of Harry Potter's strong reaction to the dementor.

Lupin returned to the cabin. He glanced around at them and felt his lips pulled upward in a small smile; he could feel the stretch of his skin where the diagonal scratch marks from when he had been bitten marred his features.

"I haven't poisoned that chocolate, you know," he said gently. This had to be a cautious bunch if they didn't devour chocolate immediately, as any of the children he grew up with would have. Really, what thirteen-year-old disliked chocolate?

"We'll be at Hogwarts in about ten minutes," he said, making his way over to his seat. He looked at Harry, who had the window seat directly across from him. He still looked quite pale.

"Are you all right, Harry?" he asked softly. He hadn't seen the boy since Lily and James had held his first birthday party in July twelve years ago, but he couldn't help but feel somewhat protective of his friend's only child.

Harry muttered something about being fine and Lupin leaned back in his seat, looking out the window and thinking of how briefly he had known Harry as a child and of how little the boy must know about his parents. He felt guilty in a way, for having spent so much time with Lily and James when Harry only had a year that he probably couldn't even remember.

When they arrived at Hogsmead Station, Remus let the students leave before gathering his things and heading for one of the thestral drawn carriages. He got into one of the last carriages, which he ended up having just to himself. He looked up through a grimy window at the wondrous castle before him, and was again assaulted by memories of the Marauders, the many pranks they had pulled, and the many times they had narrowly avoided trouble. He wondered what had become of their old map.

When he got out of the carriage, the first thing he saw was Harry and Ron glaring at a pale faced boy whose look just screamed Slytherin.

"Did you faint as well, Weasley?" said the unsavory boy who had two thug-like boys on either side, looking like body guards. "Did the scary old dementor frighten you too, Weasley?"

"Is there a problem?" he said calmly, looking from the Slytherins to Harry and the Weasley boy. There was an obvious rivalry between the two boys, and Lupin was reminded of the hate James and Sirius had shared for Snape.

The pale boy looked at him scornfully. "Oh, no…uh…professor," said the boy, making his status seem more like an insult than a job.

He waited for the boys to leave before making his way to the staff table in the Great Hall. He wasn't exactly pleased to find that his seat was next to his childhood enemy: Severus Snape.