A/N: Please go to Chapter 18 'Exposed' and scroll down to read the 4th last paragraph where I introduce and explain an important character (which I went back and rewrote in). Please also go back to Chapter 3 'Return of the Mirror' and read the A/N I posted there which is very, very important. Thank You.

Chapter 22: Acies Apertum

Professor Mysticus swept gracefully to the front of the room and faced her students. She smiled warmly at them and began to speak. She had her hair tied up in exactly the same way as she had worn it the other night and she was wearing beautiful blue and navy robes, which seemed to flow about her body adding to her elegance. She looked around the classroom, taking in the faces and gave Harry, Ron and Hermione a quick, excited wave when the others weren't looking. Hermione waved back discreetly and Harry suddenly remembered where he knew the new Professor from. She was a member of the Order and had been at the Christmas Party!

"Right well first things first – I'm Talia Mysticus," she said, addressing the class once they had settled into their seats. "I've never taught before so I'm very sorry if some of the things I do are a little different. I did do Potions at N.E.W.T level but I do not claim to be as excellent as Severus Snape at it."

At the mention of his name Draco's face shadowed and he exchanged dark looks with Crabbe and Goyle.

"Right, well the next topic to be covered in your Curriculum is-"

But before she managed to finish her sentence, Draco interrupted, without bothering to raise his hand. "Why did Voldemort take Snape?"

The whole class turned to look at him and Professor Mysticus sighed. She'd taught 3 other classes this morning and they all seemed to think she knew Serverus' whereabouts. "I know no more than The Headmaster has told us."

Draco rolled his eyes. "He must have explained what happened, at least to the Professors," he sneered. "Or didn't he trust you?"

"Professor Dumbledore has indeed briefed us on the circumstance," she replied, ignoring his last remark. "But I'm afraid we do not know much."

"What do you know?"

The whole class was listening with interest. "Well," she paused, thinking her next sentence out cautiously, "It's rather complicated. You-Know-Who believed Severus Snape to be his spy, whereas in truth he was actually Dumbledore's spy. Much like a double agent. It seems You-Know-Who figured out what was going on – and we can only guess what Severus Snape is going through at this very moment. Now if you please, I do have a lesson to teach. You are due to learn about the Truth Potions. Who knows how many there are?"

Hermione's hand, predictably, was the first to shoot up, but Lavender's and Pansy's also wavered up to shoulder height.

"Yes? Miss er – ?"

"Hermione Granger. There are 5 Truth Potions in total."

"Correct, well done. 10 points for Gryffindor. I'll leave the rest of the questions for later, I think it would fairer to let you read about the Potions first. – so on page 194 of your textbooks there should be a list of all the Truth Potions in order of strength, along with some distinguishable characteristics and of course, the effects. Can you please copy those down on your parchment and at the end of the lesson I will demonstrate the effects of one of the lesser Truth Potions, if I have a daring enough volunteer," she chuckled a little bit and sat down behind her desk. "You may talk if you wish but please keep your voices down."

The class immediately started shuffling through the text book and unrolling parchment. Harry looked at the page they had been instructed to copy.

In order of strength, the 5 Truth Potions are: Denarro (weakest); Accuratio; Fessus; Sincerus; and Veritaserum (strongest). Below you will find more details of each of these:

Beside each description was a coloured diagram of the potion in tiny crystal bottle, every single one still, flat and undisturbed, although each had a different colour or consistency. Harry dipped his quill into the ink and began writing,

After nearly minute, when Harry was underlining the word 'Accuratio' Ron started chuckling and both Harry and Hermione looked to see what had amused him. His quill was hovering at the end of the sentence describing the texture of Accuratio. " 'Lots of tiny bits of sand floating in my mouth' " he quoted. "Haha! Funny!"

Harry grinned to. "Yea. I'd hate to drink that!"

Ron nodded, his eyes sparkling merrily.

"Fessus is worse though," Hermione said fairly. "Look at what it says about that one."

Harry's eyes scanned the paragraph for descriptions about texture or taste of the 3rd Potion and after a second he found what she was referring to.

Most drinkers expressions show that of revulsion and this is believed to be due to the foul stench and taste of Fessus. There have been cases of nauseous upheavals, some lasting for days after drinking this Potion, hence the administering of it is kept at a minimum.

"Aw, yuck!" Harry said with a shudder. 'That's manky!"

"Gross!" Ron exclaimed. "I'd never drink that!"

"Oh yea? You drank Polyjuice," Hermione reminded him.

Ron's face contorted with disgust. "I know. But this sounds worse. At least I didn't throw up then."

Hermione smiled, "Well, I felt like I was about to."

"That could have been because you turned into a cat though," Harry said sincerely. "That would make most people sick wouldn't it?"

The three of them laughed and Harry continued copying up the characteristics of 'Accuratio' which (like Denarro) also seemed easy to lie through.

The general chatter of the class increased, though Hermione remained, bent resolutely over her parchment. Harry had moved onto the 4th Potion when Ron sighed, flexed his fingers and resumed writing.

As Harry copied up the next paragraph, Harry found out that the symptoms of Sincerus were much like the one's he'd seen Barty Crouch Jr suffer. There was the trance like mode, for one and the fact that even accomplished wizards had failed to lie under the influence of 8 – 20 drops of it. There were some pretty nasty side-effects too, and as he listed them, Harry found himself wishing he'd never have to take Sincerus. Or for that matter, Veritaserum, which undoubtedly was going to have worse side effects than concussion, loss of appetite, dizziness, trouble with speaking, balance difficulties and minor seizures ... and he also doubted Veratiserum's side effects would wear off after 24 hours either.

Harry dipped his ink in his bottle and turned automatically to see how much Ron had written. When he looked up, however, he was distracted my Professor Mysticus walking directly towards them.

"Hello," she said, smiling mischievously.

"Hi Professor," Hermione said.

"How are you going with your writing?" she asked bending down to look at Harry's parchment. Harry was about to reply when she whispered, "Been having any nightmares?"

Harry's stomach turned. "Er – yea. It was about-," he looked wearily around the room and lowered his voice. "Snape."

"What happened?" she asked urgently, turning her enthralling eyes to look right into his.

Harry's breath caught in his throat with a jolt, and he suddenly found he couldn't look away. He couldn't see anything except the kaleidoscope of amazing chocolate shades and the gentle curls of her thick, black eyelashes. Immediately he was overcome with dizziness and felt an irresistible urge to fall forwards into the depths of her eyes. They stared at him, piercing his mind and drawing all air from his lungs. He'd never felt anything like it. It was like being under a spell. He couldn't look away – he couldn't see anything else. The world was irrelevant now... and the eyes were unblinking.

"What happened in the dream?"

It was hard to think. Even the simplest things like breathing required concentration now. Her eyes were captivating, he didn't want to look away, they were beautiful. "Er - he's alive," Harry answered breathlessly. "They're trying to get him to talk. Lucius, it was Lucius torturing him."

Professor Mysticus suddenly looked away and Harry came crashing back to reality, feeling strangely disorientated. He took in a strained breath and blinked, steadying his mind. The room was so cold, and plain. Those eyes, he wanted to look back in those eyes.

"I think you'll have to talk to Dumbledore later," she told him.

Harry nodded numbly. His head was returning to normal now, and he looked around shakily to Hermione and Ron. They were busy writing and didn't seem to have noticed anything out of the ordinary.

Forcing his attention back the parchment he copied down the final paragraph.

Veratiserum
This is the most powerful of all the Truth Potions. 3 drops is the accepted dosage, as this is very rarely thrown off, even by the strongest of wizards. Any more than 4 drops often results in a mixture of all the other 4 potion's side effects, any more than 6 drops can cause permanent damage to one's mind and 10 or more drops could kill a man.

Vertiserum has the appearance and consistency of water and unfortunately there are no definite ways to tell them apart. Vertiserum will force the entire truth out of the drinker and once the effects wear off, they have no memory of what they have confessed. It is strictly controlled by the Ministry and anyone found in possession of it is subject to questioning.

Sighing and straightening his back, Harry sat back in his seat. Hermione had long since finished and Ron was copying up the last few lines.

The rest of lesson was far more enjoyable than the half an hour they'd just spent writing. Professor Mysticius held true to her word, and gave them a demonstration of the Potions. She told Millicent to lie on purpose, in order to show that it was indeed possible and when Seamus stepped forward she told him to both lie and tell the truth without saying which he was doing. She then challenged the class to identify whether he was being honest or not. By the end of the lesson only a small minority of the class could tell a lie apart from a truth (and Harry, who was totally at sea with it, had a feeling that their success was more a result of lucky guessing than anything else.) Seamus sat down, beaming. Professor Mysticus handed him a thick red coloured potion and told him it would clear up his light-headedness before turning to her class and announcing they had no homework.

Later that day, Care of Magical Creatures and Transfiguration aside, when the rest of the students swarmed down to the Great Hall for dinner, Professor McGongall pulled Harry aside, shooing Ron and Hermione to continue walking, and lead him up to Dumbledore's office.

"Ton Tongue Toffees," Minerva said sharply. Harry smiled slightly as the gargoyles spring to life and she strode onto the staircase, Harry following closely.

When they reached the top she simply knocked on the door and Dumbledore called for them to enter. She opened the door, nodded to the elderly Headmaster and turned on her heel, leaving Harry alone in the office.

Dumbledore coughed, cast a silencing charm on the room and then smiled. "Sit down," he said, pointing his wand at a large, red, squishy chair which had just scooted out from the corner. Harry did as he was told and then looked across at Dumbledore, wondering how to start. Dumbledore, however, did the starting for him.

"Harry, the first thing I want to talk to you about is the dream you had last night. Professor Mysticus tells me you saw Lucius torturing Professor Snape?"

Harry nodded.

"Would you mind explaining to me in detail?"

Harry did. At the end of it Dumbledore merely nodded and his beard twitched as he pursed his lips.

"Thank You. And I must ask you, if you have another dream like this – please find Professor Mysticus and tell her."

"Professor Mysticus? Why?"

Dumbledore merely smiled. "I can trust you to report to her, as soon as possible, after learning something? It will be very useful for the Order."

He nodded, but before Dumbledore had the chance to continue, Harry interrupted. "Are we trying to help him?"

"Help Professor Snape out of Azkaban you mean?" he asked calmly. Harry nodded again.

Dumbledore drew a deep breath and pushed his glasses up his nose. "Of course we are, Harry. The Order is working on a plan as we speak. The outcome – I cannot predict. We shall have to see."

Feeling a strange surge of dread, Harry simply nodded once more, feeling a little light-headed already, and waiting for Dumbledore to ask something else of him.

"I feel I should apologise," he said suddenly. Harry looked up startled. "For sending you to 12 Grimmauld Place. I was aware it was a place you'd rather never visit again ... but alas, logic overruled, and in all honesty, it was safer for you to be there."

Harry hung his head, trying to wipe the disdainful look from his face. He'd been very angry at Dumbledore for making him go there, but he was desperate not to show it. The old man's voice was full of such honesty and compassion, that Harry couldn't find it in himself to discard the obvious beg for forgiveness.

"The Burrow was not an ideal place to stay, and unfortunately, out of all the possible accommodations I considered sending you to, the Head Quarters offered the most protection. I realise it must have been difficult for you and I am sorry." He paused again and drank from a glass of water while Harry mumbled something about it being ok.

"I think, Harry – we will be talking for quite some time. In fact, I think it would make sense for me to bring some food in, after all, the rest of the school is dining right now, why shouldn't we?"

Harry smiled weakly, wondering what sort of lengthy discussion the Headmaster had planned, and Dumbledore tapped his wand on the edge of his desk. Seconds later, with a loud crack, a house-elf appeared at his side. "Please bring up two meals and a jug of pumpkin juice, Auris." The house-elf nodded, his overly large ears flapping over his eyes. "Yes, Headmaster, sir," and he was gone with another crack.

Dumbledore shifted in his seat, making himself comfortable. "I want to talk to you. I'm not sure exactly what about – but there is much we need to discuss, too much that has been left unsaid. I feel the conversation we had at the end of last year did not offer you enough closure, or information for that matter. However, I thought it best that I did not burden you with any more words when you were in no state to listen. As soon as you left the room, of course, I realised I had done it again. Only minutes before, I had been telling you that one of the worst mistakes I ever made were not telling what you needed to know soon enough... and then I did it again, straight away. Perhaps I can get away with blaming my age for that," he said his eyes twinkling. Harry smiled at him.

"It's ok. Um – I'm sorry for breaking all your things," he muttered sheepishly.

Dumbledore waved a hand in the air to show it was forgotten and totally understood. Feeling a little better Harry leaned back into his comfortable chair. There was more silence for a few moments and Harry observed the orangey glow of the setting sun, gleaming over the blackened peaks of the forest. Auris reappeared with a sudden noise and placed two trays on Dumbledore's desk. Less than a second later, an additional elf arrived and settled the jug next to them.

"Thank You," Dumbledore smiled. Both house-elves bowed in unison and vanished before they had even finished standing up again.

Albus smiled at Harry and pointed welcomingly at the tray furthest from him. Harry picked it up and placed it on his lap. It smelt wonderful. Dumbledore let him drink some Pumpkin Juice before continuing with their conversation.