Disclaimer- I don't own Harry Potter.

So, this fanfiction is basically going to be an AU of, instead of Lockhart, Lupin teaching DADA in Harry's second year. I'm not going to rewrite the parts that aren't changed- namely, the first few chapters of the books. It'll start out looking fairly similar to the actual book until things start happening, when it should take a turn.

Enjoy! :)

Harry and Ron have taken the Ford Anglia to Hogwarts, only to find themselves about to crash into the Whomping Willow.

"WATCH OUT FOR THAT TREE!" Harry bellowed, lunging for the steeling wheel, but too late-

CRUNCH.

With an earsplitting bang of metal on wood, they hit the tree trunk and dropped to the ground with a heavy jolt. Steam was billowing from under the crumpled hood; Hedwig was shrieking in terror; a golfball-size lump was throbbing on Harry's head where he had hit the windshield; and to his right, Ron let out a low desperate groan.

"Are you okay?" Harry said urgently.

"My wand," said Ron, in a shaky voice. "Look at my wand-"

It had snapped, almost in two; the tip was dangling limply, held on by a few splinters.

Harry opened his mouth to say he was sure they'd be able to mend it up at the school, but he never even got started. At that moment, something very large and heavy came hurtling at the side of the car, stopping barely an inch from them. Harry looked over at Ron and saw that he had his mouth open in a silent scream.

"Come on," said an unfamiliar male voice. "Let's get you out of there before the tree comes alive again, shall we?"

Strong arms pulled Harry out of the car and dumped him unceremoniously on the ground, and he watched as a dark figure did the same to Ron.

"Hedwig!" he said loudly. "My owl, she's still in there! And our trunks, all our schoolbooks and stuff!"

"I know, I know," said the stranger, quietly amused. "I haven't forgotten."

The stranger pointed his wand at the car and the trunk flew open with a bang. Harry stopped paying attention to what the stranger was doing as he looked up and noticed, with horror, a huge tree's branch immobilized not three feet above him. Looking around, he saw that they were still under the branches of a huge, menacing trees with giant, dangerous branches. It quivered silently, as though it knew they were still within its reach, if only it could move.

Harry began backing away quickly, Ron next to him, clutching Scabbers in his left hand, his broken wand in his right as he furiously scooted out of the shadow of the tree. They watched the stranger heft their trunks out of the back of the car and send them zooming towards Harry and Ron, where they skidded to a stop in front of them. He picked up Hedwig's cage and let her out; she screeched and sped off towards the castle without a backward look.

The tree was beginning to move again, but the strange took no heed. He climbed in the driver's side of the Ford Anglia, only to be forcibly ejected from it as the car back away itself and sped off into the Forbidden Forest. Harry glanced at Ron, whose face rapidly drained of color.

"Dad's going to kill me..." he moaned.

The tree gained full mobility just as the stranger jumped out of range, still holding Hedwig's cage. It tried vainly to reach him, and when it became clear he wasn't coming back, beat its branches against the ground in frustration. At this point, however, Harry had stopped paying attention to the tree.

"Who are you?" asked Harry, hoping his voice didn't sound as shaky as he thought it did.

"Professor Lupin, your new Defense Against the Dark Arts teacher," said the stranger picking up a small, battered case held together with a large quantity of neatly knotted string from the grass. "I was just spending a little quiet moment before the feast observing the Whomping Willow-for nostalgia's sake, you see- when, lo and behold, I saw a car fly right into it. I arrived just in time to see you safely out of there, although, I must add, it was a most curious way to make your entrance."

"The platform was blocked off-" began Harry, but Lupin waved it aside. It was hard to tell in the dark, but Harry thought Professor Lupin looked quite amused.

"Let's get you up to the school, I'm sure you'll have ample time to tell your story there."

Grabbing his trunk and taking Hedwig's cage from Professor Lupin, Harry realized with a sinking feeling that they were probably in a lot of trouble. They headed towards the great oak front doors, growing gloomier by the second. If only the platform hadn't been blocked...why had it been blocked? And why had they been so stupid, taking the car like that?

Lupin flicked his wand when they grew near the doors and they opened to reveal the sneering visage of Severus Snape, the Potions master and Harry's would-be arch-nemesis, if only Draco Malfoy weren't in his life. Harry wasn't given time to dwell on Snape's hooked nose or greasy, shoulder-length hair, as Professor Lupin pushed them inside and stepped in front of them protectively.

"Lupin," said Snape, his eyes narrowed in the intense glare of dislike that Harry usually associated with Snape's hatred of Harry himself. "I see you've found Potter and Weasley. If you'll let me take them off your hands, I'll just bring them down to my office to...administer punishment."

"Severus," said Professor Lupin pleasantly. "There's no need for that. I was planning to take them to see Professor McGonagall, as she is their head of House."

Snape's lip curled. "If you're sure."

He apparently had nothing more to say to Lupin, Ron, or Harry, because he briskly turned around and headed back into the Great Hall.

Harry looked at Professor Lupin for the first time in the light. He was wearing an extremely shabby set of wizard's robes that had been darned in several places. He looked ill and exhausted. Though quite young, his light brown hair was flecked with gray. If Harry hadn't seen him freeze the Whomping Willow, he would have wondered if Lupin was up to the job.

"Stay out here," Lupin advised them. "If you go anywhere, things will be even worse for you. I expect I'll see you in class, Harry, Ron."

From Snape's mouth they would have taken that as a threat and bristled in reply, but from Professor Lupin it sounded much more like a warning. He smiled at them and they watched him stride into the Great Hall.

"How did he know my name?" asked Ron in complete wonder. "He's brilliant, mind you, but who just goes out and looks at mad trees for fun?"

Harry rather agreed with him, but he never got the chance to say so, because Professor McGonagall appeared at the doors to the Great Hall. Harry felt his stomach drop at the sight of her thin, angry mouth. Ron let out a small whimper.

She marched them to her office, where they sat, feeling suddenly ashamed of themselves. She told them to sit and tell their story, which they did.

"-so we had no choice, Professor, we couldn't get on the train."

"Why didn't you send us a letter by owl? I believe you have an owl?" Professor McGonagall said coldly to Harry.

Harry gaped at her. Now that she said it, it seemed the obvious thing to have done.

"I suppose it never occurred to you that you were seen, did it?" she said. "I believe Professor Snape has a copy of the paper it's in, if you are dying to read of your exploits. If not, it should suffice for you to know that seven Muggles saw you. Do you know how serious your actions were?"

And suddenly, they did. It was only when they were back in the Gryffindor common room, where everyone clapped on their arrival and they suddenly felt like heros that they stopped feeling bad.

Reviews are love! :)