Disclaimer: I do not own Harry Potter and never will. Too bad for me.

A/N: Oh my gosh! I never believed I would get so many reviews in such a short period of time. I'm so grateful to all my reviews. They increase my self-esteem by a ton. :) Hope you like this chapter!

What? No. That was impossible. And of all people, why him? He knew what was happening, but he couldn't accept it, no way. Frantically, Harry began searching for some signs that this wasn't true. But as he looked in the mirror, he could find none. Greasy black hair. Long, black robes that were actually covered in mothballs. Hooked nose. Those lips that would curve into either that trademark smirk or sneer. Pasty white skin. There was no doubt about it; Harry Potter was stuck in the body of Severus Snape. He screamed, loud.

Severus woke up gradually, confused. Why was he on the floor? And why was his classroom covered in purple goo? Wait! His classroom! Potter. He was going to kill that brat. He stood up, but that abrupt movement caused his vision to blur. He straightened his glasses, wait glasses? He pulled them off and examined them, and his heart stopped. Those were the trademark James Potter glasses, black with round lenses, although they did look cheaper. Realizing what this meant, Severus numbly, lifted his fingers to his forehead. And there it was, the lightning bolt scar. Severus had turned into the Boy Who Lived. He felt like screaming, but knew it wasn't the way for a professor, even one in a student's body, even the student he hated most, to act. Instead, he drew a sharp breath and went to find that Potter boy.

When he heard himself screaming, Severus wanted to hide. He knew it was a girly, high-pitched scream, and that was one of his most embarrassing traits. But, he steeled his courage and walked up to Potter, or rather, himself.

"Potter! What is the meaning of this?" he demanded.

"Professor? But….NO! This isn't real. I'm in the middle of a dream, someone is going to wake me up because I've been screaming, this is all just a bad, bad dream. Pinch me—" Potter blabbered, but was interrupted when Snape jabbed him sharply in the side. Now, anyone walking by would have thought this spectacle comical, a student (none other than Harry Potter) poking a professor (none other than Severus Snape) in the side and them referring to each other by their own names. Or, the person walking by might have found it suspicious. But, luckily there was no one around this late at night, except for maybe Filch, but he wasn't in the dungeons.

"Potter. Listen to me. I am in your body. You are in my body. It is your fault. I don't know how to reverse this because it has never happened before. I have a NEWT Level Potions class to teach tomorrow at nine o'clock AM. But I am in your body. You cannot teach Potions because who knows how badly you'll mess this one up?" Severus drawled out slowly as if speaking to a three year old. Potter grimaced.

"You startled me! If you hadn't yelled out my name, none of this could have happened!" Potter protested.

"Quiet, boy!" Severus yelled. He was surprised to see Potter grow blanch at the word boy. What was going on?

"Professor, how do we get back?" Potter asked.

"We're going to have to tell the Headmaster. He might have a way," Severus answered. He knew that going to Albus would mean stomping on some of his pride, but he didn't trust himself in trying to fix the problem. What if he was stuck looking like a good-for-nothing Potter forever? But, he was also surprised that Potter, as pale as he already was, paled even more.

"Professor Dumbledore hasn't talked to me at all this year; actually, he hasn't even looked at me. I don't think he's going to be very much help at all," Potter protested.

"Potter! Stop talking and just follow me! We're wasting time, and I don't want to spend more time in your body than I have to!" Severus barked. Unexpectedly, he saw Potter bite back a retort. Weird. The Potter before last night would've cheeked him. Was Potter being sympathetic towards him? Well, that was great. He didn't want any compassion, especially from anyone with the last name Potter. "Ice Mice." The gargoyle jumped aside, and together they entered Dumbledore's office.

Harry steeled himself as he entered the vast oak door. He was ready for this. He just hoped Dumbledore would actually make eye contact with him.

"Ah, hello, Severus. I see that you've brought Mr. Potter here and you've gotten yourselves in some sort of skirmish. How did that happen?" he asked, directing his questions at Snape. Harry's jaw dropped.

"How did you know?" he asked, bewildered. Dumbledore fixed his gaze on Harry's right shoulder.

"Well Mr. Potter, it is quite amusing to be addressing Severus as a Potter, but I could tell from your stances. Severus, for example is scowling right now with that special scowl that only he ca do, and when you walked in, I noticed that you weren't sweeping your robes while walking as Severus usually does," Dumbledore remarked cheerfully.

Severus scowled again, but Harry smiled. He was glad Dumbledore still had his sense of humor.

"So how are we going to get back, sir?" Harry asked. Dumbledore scratched his beard.

"When you added those sprigs of lavender to your potion, it changed the potion to something else, called a soul switching potion. This was invented by Gary Heisendinger during the first goblin rebellion. He had hoped to pour this potion into their goblets and some into his own men's to try and stop the goblins from attacking. Needless to say, as I'm sure you learned in Professor Binn's class, it did work, and the wizarding world was saved. People for many generations have tried to make this potion numerous amounts of times, but you had to have the potion that reduced swelling brewed to a certain second, or else it would all fail. However, you dropped it in just as the second ended which caused the explosion. There is a way to reverse this, but Mr. Heisendinger's reverse potion takes four months to brew, and only if we start now. The longer we wait, the longer it will take to brew. Some of those goblins were stuck forever because they waited until the end of the rebellion, which lasted seven years. And, by the time the potion is done, you, Mr. Potter, will have OWLS the next week, and Severus has potion classes to teach, not to mention certain, ah, meetings," Dumbledore finished his speech by offering each of them a lemon drop. Harry considered this.

"We should really start the potion now. Do you need any of my help?" Harry asked.

"No!" Severus cut in. "Potter might mess it all up, and I'll be stuck in his scrawny body forever!"

"Severus and I will attend to all matters involving the potion. Tomorrow's Potion lessons will be cancelled, and we can fake that Professor Snape has an illness contracted potion that exploded in his room last night. This will give you the time for Severus to teach Harry his lessons, which in turn Harry will teach to the students," said Dumbledore.

"But I can't teach! I don't know how! And if I had to teach, it definitely wouldn't be Potions! It's my worst subject!" Harry objected.

"If I have to attend fifth year classes in a house none other than Gryffindor, then you will teach students in Potions, Potter," Snape said. Gryffindor! But what about Ron and Hermione? What happens if they figure out I'm stuck in Snape's body, and he's stuck in mine? Those questions came pouring into Harry's mind. When he voiced them out loud, Dumbledore smiled and Snape groaned.

"Mr. Weasley and Miss Granger will not be informed of this change, Harry. Usually, I would advise you to tell you friends, but people can end up overhearing things, and then this information might be passed on to Voldemort. Severus, you will have to act exactly like Harry, and friendly towards Mr. Weasley and Miss Granger. And Harry, you must act exactly like Snape, showing favoritism towards the Slytherins and being a godfather to Mr. Malfoy," said Dumbledore.

"I do not show favoritism," Snape protested. Harry and Dumbledore looked at him. "Fine," he sighed. "I'll be a Gryffindor if Potter is Head of Slytherin."

"And out in public within earshot of other people, you'll have to call each other you own names, or else our whole plan may be ruined," Dumbledore added. Harry and Snape reluctantly nodded.

"Please just hurry up with the potion," Harry begged.

"I'll get to work on it straight away. And you should be getting some sleep, Harry. After all, you do have an illness contracted from an exploding purple classroom. The password is Pureblood."

"And you have to clean up that mess in two days. After all, you made it," Snape added. Harry groaned.

"Yes, professors."

"Remember-be civil," Dumbledore advised. "Good night, Mr. Potter, or Severus.

"Call me Harry, please, when we're alone," Harry said with a grimace. He exited Dumbledore's office with a sinking feeling.

A/N: This was a fun chapter to write. And about Dumbledore and how he knows immediately, I kind of find him a wizened old man who just happens to know everything that goes on in his school. Please keep reviewing! I LOVE them!

Shu-chanX: Hey! Thank you so much! Haha, I wanted to make Harry faint again, but then I thought that would portray him as a weakling who would get scared at everything he sees, but lol, maybe not. And yeah, I've read so many fanfics that started with flashbacks or just the action, and I thought I would try nightmares XD. And in OotP, when Harry looks into Snape's memories, there is a scene where he's taunted by the Marauders and they use his own spell against him. I can see where you're going with that theory, but when Iread the book, I felt that Harry was really humiliated by what his father had done. So, I don't know if Harry wanted to redeem his father, but I felt that he wanted to tell Snape that he didn't approve of his father's actions, either, and although he was practically a carbon copy of James, their personalities were totally different. And thanks for your long review! I know, to some people it isn't considered long, but I call everything that's longer than 2 lines long. Hopefully that clears it all up. :)

Moerie: Thanks! This was sort of inspired by Freaky Friday (awesome movie, by the way, if you haven't seen it, you should check it out) and I know that soul-switching has been done before, but never between Harry and Snape :) Yeah, I'm really excited for writing about the Death Eater meetings. Voldemort wouldn't have a clue that the person sitting right next to him wanted to kill him. :)

And special thanks to: BlueWater5, Ashley Ayoub, hobesan, and Elie K for your reviews! Y'all are awesome!