A/N: As promised, a new chapter. With all luck, I should be able to keep a regular updating schedule from now on.

Good questions, again. This chapter should actually answer some of them.

The Best of All Possible Worlds

Chapter Nine: You!

"You should not have left my office," Snape said again when they were safely ensconced in the room once more. It seemed to be his second-favorite thing to say, next to "idiot boy," Harry thought, frustrated, and glaring at Snape's back. "There are too many around the school who know Mr. Potter, and would assuredly have tried to make you talk to them."

"I know, sir," said Harry. "I really don't want to stay here any longer. I only want to go home. You said that you had a potion that could help me?"

Snape turned and gave him a freezing look for a long moment, then turned away. "Yes," he said. "I will need your help to make it. I assume that you are not hopeless at making potions, as you no doubt have received advanced tutoring from my…counterpart?" He took a bottle of something dark purple from a shelf and moved towards the fireplace, casting a swift "Incendio" to start the fire.

"I…well…" Harry shuffled his feet, and hoped that Snape wouldn't look at him at the moment, since he could surely have told that Harry was lying about being a Slytherin. Luckily, Snape seemed involved in picking out the best possible cauldron. "I manage to pass the class, but I never do as well as Hermione."

Snape snorted and turned around. "Only Mr. Longbottom does nearly as well as Miss Granger," he said dismissively. "If you can follow instructions, and wave your wand when I tell you to, then you will be adequate. At least you will not play pranks while we are doing this, as Mr. Potter tends to do." He set the cauldron hovering over the fire with another wave of his wand, and dumped the purple liquid into it. There came a puff of colored smoke that had Harry holding his breath, but Snape simply reached for another bottle of ingredients, as if this were all normal.

"What is the other Harry like in class?" Harry asked, edging closer to the cauldron. If Snape was going to have him chop something up or use his wand to make the Potion, then he wanted to be ready. "I can't imagine playing pranks in your class, back home."

Snape actually gave him what was almost a smile. "That is because you are a Slytherin," he said. "My own students do not give me trouble in Potions."

Harry industriously focused on the potion.

"Mr. Potter is in Gryffindor," Snape went on, almost snarling as his hands expertly sorted various ingredients into the cauldron, "and he has a tendency to decide that every room is an appropriate stage for his cleverness. And with him he pulls Mr. Weasley, and half of Gryffindor." He gave Harry a waspish glance, as if forgetting for a moment that he wasn't actually the student he was complaining about. "He does not only look like James, but follows him in the most troublesome aspects of his personality."

"James was a prank-player, too?" Harry asked, even though he knew that much from the Pensieve scene. Again, though, that wasn't a circumstance he could explain to Snape.

"You must surely know," said Snape, frowning at him. "Unless the James Potter of your world managed to learn a trace of humility after his school days." His voice oozed doubt, thick as the viscous liquid dripping from the bottle he currently held over the cauldron.

"My parents died when I was a baby, Professor," said Harry tensely, after a moment of consideration. He didn't want to reveal this to Snape, but, on the other hand, it wasn't as though this Snape could find a way to use the information against him. "I have no idea what they were like." Not really, he defended to himself. I know that they weren't perfect shining stars, but they can't have been that bad either, or everyone would have hated them, not just Snape.

"How did they die?" Snape asked, scattering a handful of white dust in a precise circle.

"A wizard named Voldemort killed them."

The white dust filtered down in a trembling fall for a moment, and then Snape pulled his hand back and considered the potion with his head on one side. "It will need some time to cool," he said, stepping away. "We may begin the second stage of its preparation in a few hours." He put the bottle he had been using back on the shelf, then turned to look at Harry. "Are you willing to wait some days so that you may go home?"

"I meant what I said about obeying instructions, Professor," said Harry, meeting his gaze as evenly as he could. "As long as the end result is the one I want, I don't mind waiting."

Snape smiled slightly. "Good. A true Slytherin."

Once again, the temptation to comment was enormous, but Harry restrained himself.

The knock came while Harry was in the middle of chopping some unidentifiable kind of thick green root for the next stage of the potion.

Snape gave him a sharp glance. "It is no one dangerous, or my wards would have alerted me," he said. "Lower your head and keep chopping. So long as no one else knows about that disgraceful business of earlier—and that brat would not have shouted it from the towers—then we can excuse this as my keeping you for a detention." He crossed to the door and opened it.

Harry kept his eyes lowered, but his ears open. He would have been a fool not to, he justified to himself, and Snape probably wouldn't think it was very Slytherin of him, either.

"Severus," said a fluttery voice. "Oh, thank Merlin. I wanted to talk to you immediately. You know, ever since—"

"Sybil," said Snape, very coolly. "I would be more than pleased to discuss this with you, but I have a student serving detention at the moment, and I do not think the things you want to discuss appropriate for a student's ears."

Harry gagged for a moment. Professor Snape and Professor Trelawney? Ick.

But then his mind went back to the strange warning his own Professor Trelawney had given him before he ventured out into the storm and the way to this world. Come to think of it, his own Snape had warned him, too. Something about death, which obviously hadn't happened, but Harry didn't think it was entirely unconnected. He couldn't afford to, since he had no other clue how he might have come here.

He raised his head from the roots and edged sideways, trying to see Professor Trelawney. He just made out the upper corner of her face, as she nodded rapidly in time to Professor Snape's words.

"Of course, Severus, of course," she said. "But I don't think that we should leave it much longer. Who knows what might have come through?"

Snape's voice got even tighter, colder, and softer. "Anything, Sybil. You were right before. You will be right again. You always are."

Harry snorted softly to himself. Yeah, figures that this version of Hogwarts would get the competent Professor Trelawney.

"But this matter is sensitive, and, I do not think, appropriate to bring up in front of a student," said Snape, and turned around, as if to make sure that Harry was where he should be, chopping roots.

Harry wasn't. Harry was in the middle of the room, staring. Even as Snape's startled glance fell on him, Trelawney's went past Snape like an arrow. It fell on Harry's face, and Harry jumped slightly as he saw the way her eyes widened. He'd swept his fringe back out of his eyes when he looked up, so she could see his scar. He supposed it was right of her to be a little surprised.

None of that excused the way she started shrieking next.

"It's you! I knew something like this would happen when I saw the storm brewing last night! I would know that scar anywhere. I saw it in my visions!" She turned around, all but putting dents in Snape's arms as she clenched them. "It's him!" she wailed into his face.

Snape was still struggling to free himself from Trelawney when Harry took a long, deliberate step forward, remembering the way that Snape had jumped when confronted with his scar last night. Something was happening here, and he wanted to figure out what. There were already too many unanswered questions floating around in his head.

"What do you mean?" he demanded. "Who am I?"

"Shut up, idiot boy!" Snape hissed at him.

"The one I saw in my visions," Trelawney sobbed hysterically. "The one who was going to face and fight Voldemort—that terrible, terrible man, the one I ran to get away from. But nowhere was far enough or safe enough, was it? Was it?" she screamed, appealing to Snape again, as far as Harry could tell.

"What vision did you have of me?" Harry demanded.

"The one with the power to vanquish the Dark Lord will be born as the seventh month dies," said Trelawney, her voice abruptly as spooky as the one she'd had—no, that the other Trelawney had had—in Harry's vision of her in Dumbledore's office. She shuddered, as if she, too, found the voice frightening, and suddenly her eyes were clear again and her tone normal. "That one. I have never forgotten it."

Snape was hissing like an enraged basilisk now. Harry felt like doing the same thing. He turned towards Snape, feeling much as he had that last evening at home.

"Did you know about this?" he asked. "Did you know what world I came from, where I got the scar, what happened between me and Voldemort?"

"Of course not," said Snape. "It was Sybil's vision, Sybil's prophecy. She has mentioned it to me often enough that I have grown tired of it. The one vision of hers that ever went awry, she said. But why would I know more of it?" He watched Harry, his eyes wary and guarded.

"Of course he knew about it," said Sybil shrilly. "Why shouldn't he? He came through the storm with me, after all."

Harry jumped back and drew his wand. Snape's was already out, though, which gave him enough of an advantage to cast a calm "Stupefy." However, an armful of Professor Trelawney prevented it from hitting Harry straight on. He felt his left arm tingle and go numb, and thanked Merlin he held his wand in his right hand.

"No," said Harry, pointing his wand at both of them and ignoring the way Professor Trelawney screamed and flinched. "I want to know exactly what is going on, and I want to know now."

Trelawney promptly started babbling. "We were both born in another world. But then I had that vision of Voldemort and his bane, and—other, darker things. I knew bad times were coming, that I couldn't stay there. So I went to Severus and told him the truth, since he was the only one who could brew the potion to move me between worlds. And then he told me that—"

"Obliviate."

Professor Trelawney stopped talking and stood with her mouth very slightly open. Snape pushed at her, and her arms dropped limply to her sides. Harry watched, his head still bursting with questions, but many more answers than before. He swallowed, once again feeling a little sick to his stomach.

"You will remember nothing of this conversation, you silly woman," said Snape evenly. "The storm was indeed set loose the other night, but no one came through. I reassured you of that, and I am sending you back to your rooms. Do you understand?"

"I do," Trelawney whispered.

"Very well. Good night, Sybil." Snape opened the door, and Professor Trelawney staggered through. He shut it behind her, and for a long moment, there was silence.

Then Snape turned around.

Harry was ready, though, and dodged the first hex that Snape cast at him, trying a quick "Expelliarmus!" of his own. Snape dodged that one, and laughed softly, in a way that made Harry far more afraid of him than if he had cursed.

"Serpensortia!"

The snake that came out of his wand looked less angry and more calculating than the one that had shot out of Draco's wand second year. It came slowly towards Harry, hissing its enjoyment to itself. "Hungry, ssso hungry."

"Go away," Harry hissed at it, irritated that he was being forced to reveal his Parselmouth gift. He looked up to meet Snape's astonished eyes, then back at the snake. "I don't have time to fool around with you."

"You could have been more polite about it," the snake whinged, turning and crawling into a corner of the lab.

Snape was still eyeing him speculatively, and Harry nearly got him with a full-body bind. He raised a shield in front of him that deflected that, though.

His next spell came as a surprise to Harry, who had thought it would be another Memory Charm, and he reacted slowly enough to let it hit him full on.

"Imperio!"

Harry felt a dreamy, floating feeling invade his mind, for about half a minute. Then he fought it off. For the first time, though, he didn't make his defiance known immediately. This could be useful, he thought, shocking himself with how coldly he reasoned, if Snape thought Harry was under his control and Harry really wasn't.

"You will not question me about my reasons for abandoning my own world," Snape demanded. "My reasons are my own."

"Yes, Professor," said Harry, doing his best to imitate the dull tone that he remembered from fourth-year DADA.

"And you will go and drink the potion that has been brewing in my cauldron for the last few hours."

Harry felt a churning panic seize him—who knew what an unfinished potion would do?—even as he replied dully, "Yes, Professor," and walked towards the cauldron.

What was he going to do now?

Well, whatever it is, I have about five steps to figure it out.