At first, and rather understandably, Draco Malfoy hadn't believed a word of what the frantic house elf by the side of his bed gabbled to him in a barely audible whisper. The idea of Blaise Zabini being a killer was absurd. He was evil, no doubt, and Draco knew that Zabini was the name of another few Death Eaters in Voldemort's ranks, but Blaise was sixteen years old. However bad he was, he wasn't a murderer. Especially not his own sister. There was also the issue of the message being delivered by his old house elf, Dobby, and things between them weren't exactly friendly. Dobby could hardly look Draco in the eye, and Draco was dying to give off some scatty comments.

But eventually, Draco had agreed to at least go with the elf to see Professor Snape. After the professor's explanation, things were making a little more sense. Of course, Snape's suggested plan of action wasn't quite so easy to absorb.

"You're not serious," said Draco, staring at Professor Snape's dark silhouette in the entrance hall.

Snape smirked at him. "I certainly am. There is no other place in the entire school where the water supply can possibly be accessed."

"But - you don't know when he's planning to do this," said Draco, with wide eyes. "You're not suggesting I sit by the lake twenty-four hours a day."

"I certainly am," said Snape, again, smiling even more. "Under a disillusionment charm, of course."

"But - I have classes to go to!" said Draco. "What about my studies? People are going to notice if I'm missing, Professor. Nobody's going to just shrug it off."

"The rest of the school shall be told that you had to leave school quickly because of a problem with the Malfoy inheritance," said Snape, smoothly, watching Draco with that smile still in place.

"But there is no Malfoy inheritance any more," said Draco.

"Precisely the problem," said Snape.

Draco paused, just staring at the professor, and then he said, "This is crazy. No offence Professor, but first of all, Blaise's own sister is dying. Secondly, Blaise isn't a murderer. Thirdly, it's just... what if somebody finds out that I'm lurking around the lake under a disillusionment charm? Blaise will know, it'll all be ruined, and if I can't explain why I was there, I'll be expelled."

"Malfoy," said Snape, simply. Draco knew that was a bad sign. Snape normally reserved that tone for people who were going to listen to what he had to say, or else. "I am your head of house, and this assignment is something that is very important. If I asked you to grade some papers for me, you would, correct?"

"Well... yes, but that's different."

"Not in my terms, Malfoy." Snape drew his wand from his pocket, tapped it twice on Draco's head, and Draco felt that horrible feeling of being disillusioned, like there was something cold and runny snaking down the back of his neck. "Meals will be brought down to you at appropriate times. I myself will take over from you for a few hours every day, so you can sleep. Apart from that, you are to sit and watch as though your life depends on it. Are we clear?"

Draco really, really didn't want to do this. He looked up at Snape, and with a very dishearted sigh, he said, "Yes. Sir."

"Very well. Go on, Malfoy, and remember to stay alert." Snape turned to go.

Draco paused for a moment, and then called after him, "Sir!"

"What is it, Malfoy?"

"I still need to talk to you about... um..." He put his hand on his side, pointedly. Snape eyed him suspiciously for a moment, and then realisation dawned, and the Potions master nodded.

"Yes... I'm sure we can discuss thatt at some other time."

"But - it's... well... it's sort of urgent, as in now," said Draco. "It's already starting to change."

Snape raised an eyebrow. "I believe I said we can discuss that at another time. Good night, Malfoy." And he left, breezing away down the dungeon corridor. Draco sighed, turned, and headed out of the huge castle doors into the grounds.

It was a very cold, very dark night. The storms had not completely cleared. Draco found this another reason to hate his new job even more. It was all so sudden - barely half an hour ago, he had been tucked up in his bed in the Slytherin dormitories, and now, he had been booted out into the grounds to guard the lake. They had a huge squid for that, didn't they?

Still... if it all ended with Blaise proved as the slime ball he was... it would all be worth it. For their first three years at Hogwarts, he'd almost tolerated Blaise, and even let the other boy follow him, Crabbe and Goyle around some time. He was always so quiet and insociable.

Draco remembered the day that his father had come home during the summer holidays, swept off his travelling cloak and hung it up on the bronze hat stand by the front door. "A most intriguing meeting today, Draco," he'd said. Draco always got a report from his father about what was going on with the Death Eaters. Draco had, after all, been fully expected to join the Death Eaters himself once he became legally allowed to do magic. Draco had to admit that the prospect had appealed to him.

"What happened?" he'd asked, watching his father open up the main doors into the entrance hall, and he'd followed as always.

"Our group has found some new... ah... volunteers," his father had said. They ascended the huge marble staircase in the entrance hall, winding their way up towards the first floor out of many, to the parlour. They always went there. Draco knew that if he ever returned to Malfoy Manor, he'd be able to trace their exact path, step by step.

"Oh? Who?" he'd asked.

"A young man named Zabini," his father replied. He snapped his fingers, and a long line of torches spreading the length of the corridor flickered to life. It wasn't exactly Pure Arts. Many things in Malfoy Manor were linked to his father's hand, and with a snap of his fingers, they could be set working. It was very simple magic. "He seems a good man... very enthusiastic. Unnaturally so. However, a supporter is a supporter..."

"Mmm," Draco mused, idly. "He has a son. Blaise. He's in my year at school."

"Ah, yes," said his father. "That name came up during our meeting... apparently the boy is interested as well. At last we have some more pure blood dynasties joining the call of the Dark Lord. Of course, there is a daughter... fourth year, I believe. The black sheep of the family."

As Draco Malfoy the sixth year crossed the lawns towards the lake, he remembered with a pang how he had laughed, and sneered, "Yes, I know her. Racing around the Quidditch pitch at all hours. Common as muck."

He sighed a little, banishing these thoughts from his head, as he approached the edge of the lake. It shined out far before him, like a perfect sheet of black glass. There wasn't even a breath of wind to disturb the mirror-like surface. Mentally preparing himself for a long night, he reached up, grasping a branch of a nearby tree and hauling himself into it. Once he was comfortably, he settled back against the trunk, folded his arms, and started to watch.

The hours whittled past. With nothing to occupy his wandering mind, Draco found himself getting more and more bored and sleepy. He was finally considering breaking his guard duty, and sneaking back to the castle to fetch his sketchpad or a book, when he noticed the movement in the top window of one of the towers.

Even though there was no light there, Draco could see that it was a student, standing on the windowsill, holding something in their right hand. Draco's experience of the astronomy tower was that it was cold and blustery especially at the windows, and surely, the winds whipping around the stone surfaces could easily whisk somebody away.

He sat forward in his tree, watching closely. The clouds over the moon moved, lighting up the scene, and he easily recognised that short stature, the dark hair, the pale skin. Blaise. Draco was just considering rushing for Professor Snape, when he noticed that a long rope was coiled around Blaise's wrist. The other end was tied to the windowsill.

Draco felt a surge of panic. Surely Blaise wasn't going to jump and kill himself?

As he watched, Blaise took the thing in his right hand, fumbling with it for a moment, and then he raised his hand over his mouth. A potion, Draco thought. But what was Blaise going to do? He saw the boy fling the empty phial aside, and he tensed. Draco realised just what he was going to do a moment before he actually did it. Blaise bent his legs, and pushed out with his arms, leaping away from the walls. Draco gasped and nearly fell out of the tree, knowing that in these winds, Blaise would just be swung straight round in an arc until he crashed against the castle walls and broke all his bones.

But to his eternal surprise, the boy didn't even fall. He simply glided through the air, as though skating, his robes billowing and buffeting in the winds around him. He began to sink, as though through water, the rope holding him reasonably close to the castle. Of course, Draco thought. It was Larin. The Light As Air Draft... Snape had mentioned it a few times in Potions. Naturally, Blaise couldn't be caught heading out towards the grounds. Snape would be watching for him. And so he'd gone upwards, to the astronomy tower, and he was now sinking gracefully down to the ground. It was flawless.

Blaise's legs crumpled as he hit the ground, but he straightened up almost instantly, and drew his wand. He murmured an enchantment that Draco couldn't hear, and the rope instantly burned from the ends inwards, turned to ash in moments, and was whisked away into the winds. Flawless, again. Undetectable. Another enchantment, and his weight had returned to normal.

The Slytherin boy then proceeded across the grounds. He was moving so silently and so quickly that he could have easily been nothing but a shadow, or one of the creatures from the Forbidden Forest. Draco found himself a little scared. If Blaise had gone to all this trouble not to be detected, surely he would have thought of what he would do if he was attacked or confronted.

Draco just sat and watched as Blaise advanced to the edge of the lake, then knelt down next to the water, pulling back a thick black hood. As carefully as he could, Draco started to ease his wand out of his sleeve, whilst keeping a close eye on Blaise. He appeared to be searching through handfuls of tiny glass beads, each one differently coloured and glittering in the moonlight.

Blaise had apparently found the one he wanted. He carefully tipped the others back into his pocket, and inspected the bead closely. A horrible smile had curled his lips. "I'll serve you," he murmured. "You may have lost the Malfoy boy, Master, but you will never lose me."

Draco drew his wand right at that instance, swishing it through the air with a cry of, "Petrificus Totalus!" The bullet of light struck Blaise hard in the chest before he'd even realised what was happening, his arms snapped into rigor mortis, and he fell to the ground, stiff as a board.

Draco clambered down from the tree, keeping his wand trained on Blaise. The coloured beads had spilled over the ground, and Draco realised they were not glass at all, but tiny little spherical containers, each holding a different potion. The one Blaise had been planning to empty into the lake was snapped shut in his hand, and after a few moments of struggled, Draco managed to get it out. It was scarlet, with little veins of black creeping across the bright red surface, like spiders' legs. Draco raised an eyebrow. "Palaris Prang? This is illegal, you know, Blaise... and you weren't considering dropping this into the water supply now, were you? How predictable. You should have waited a few months. Or could you not wait? You wanted to strike again when the school was full of fear over what happened to Potter and your sister... when you were still a complete no-go for suspicions about who it was. And when the whole school water was poisoned, you'd put on some big fancy show of grief for your lost sister and any others who were dead, right?"

Blaise couldn't move at all, not even pull his eyes down from their wide, staring position, but his pupils were blazing with fury. Draco chuckled, and he couldn't resist having a little jibe.

"You really should have known better, you know..." he smoothed. "And how horrible for you that it's me who catches you. Now, if this had been last year, I would have probably helped you at this. And even without my father, if you'd come to me and suggested such a thing, then well... I'd have been tempted. But no. You had to try and go for top spot while I was weak." He tucked the poison bead into his pocket, cool as cool could be, raising one slender eyebrow. "And you're going to regret that for the rest of your life."

It was hard work dragging Blaise all the way up the slope to the castle, and he had to keep stopping to tot up the full body bind, just in case, but every step of the way, he had a flush of pride and arrogance at seeing himself standing before Dumbledore - ... actually, no, before Professor Snape, and Snape was handing him a medal and saying, "A thousand points to Slytherin for catching the culprit, Malfoy, and I must say, we are all absolutely enthralled as to how you did it... truly heroic of you..."

And he would smile, and say, "Well, Professor Snape, it wasn't hard... though I did have to beat Zabini into submission, with just my fists, mind you, he'd stolen my wand, and after an hour long struggle on the side of the freezing lake, completely in the dark, I managed to get him by the throat. He confessed to his sinful deeds, and then I recaptured my wand, and I told him, "Evil never wins, Zabini!"... though please, all this attention is a little much... well, if you insist."

He shouldered open the doors of the castle, dragging the rigid Blaise through into the torchlight of the entrance hall. making sure he had his best, "triumphant but exhausted hero" face on. Snape came sweeping up the corridor from where he had been standing guard. "Malfoy! What happened?"

Draco smiled, and said, "Well, Professor Snape, it wasn't hard... though I did have to beat - "

"Yes, yes, never mind that," said Snape, grabbing Zabini by the other arm and dragging him away towards the stairs. "To the headmaster's office, Malfoy."

And Draco, looking slightly put out, took Zabini's feet and started carrying the stiff body away up the stairs, muttering something about, "Merlin, don't thank me too much..."

Blaise was propped up against the wardrobe in the headmaster's office a few minutes later. Dumbledore had managed to relax his throat muscles so they could hear his confession, and those in his stomach, so they could sit him up against something with him snapping in two. Snape had gone to fetch a good dose of veritaserum. At first, Dumbledore and Snape had given Draco odd looks when veritaserum was mentioned, but at a disapproving glance, Snape had just gone to get it.

Blaise was now just sitting, and staring hatefully at Malfoy, who was delighted in giving him sweet little smiles back. He'd already started writing the script for this particular event, when it would be used in the film of his life. Of course, some things would have to be different. A swooning group of girls should, by Draco's calculations, be coming in through the door at any moment to weep into his shoulders and cry with relief that he'd managed to survive his horrific ordeal.

Dumbledore arranged his purple nightcap on his head, and pushed a plate of fairy cakes towards Draco. "Whilst we are waiting, I'm sure you're very hungry, Draco... won't you have a fairy cake?"

Draco hesitated for a moment, then took one. "Thankyou," he muttered. The reward of a fairy cake could possibly be left out of the film.

The door opened, and Snape came in, carrying a small crystal phial full of veritaserum. Draco could recognise what it was instantly. He had a vague memory of sitting in the chained chair of one of the courtrooms in the ministry of magic, covered in bruises, both physically and mentally exhausted, as a wizard brought in a beaker of veritaserum. He shook his head to rid himself of that particularly image. Not now.

Blaise saw the veritaserum, and his eyes widened in fear. "No," he managed, breathlessly. "No, no! Professor! Don't - ... please, I beg you, please Sir..."

Snape's eyes were narrowed as he swept over to Blaise, and then he descended down on the Slytherin, like a vampire going in for the kill. His fingers grasped the front of Blaise's hair, pulling it back, and the boy's mouth fell open in shock. Snape calmly poured the phial of clear serum down his throat, unmercilessly. "Beg all you want," he snarled. "I won't hear a word."

Blaise choked, and coughed, spluttering, as his body tried to expel the veritaserum. Draco could already see its effects slowly gripping him. His eyes were glazing over, and the more he struggled, the harder the potion worked to snare him. After a moment's twisting and turning, his muscles gave in and no longer fought the draft. It washed over him completely. Snape smiled a little. "Blaise Zabini?"

"Yes," came the flat, toneless reply. Blaise's eyes flickered.

"You were out of your bed tonight," said Snape, smoothly, leaning back on the edge of Dumbledore's desk. "Carrying various, highly dangerous poisons. You planned to poison the water supply. Is this correct?"

Another flicker went across Blaise's face. "Yes."

"And you have poisoned the food in this castle on various other occasions."

"Yes."

"One of these is more than likely going to lead to the death of your own sister, and Harry Potter was nearly killed."

"Yes..." Draco found himself stung by the note of pride in the other boy's voice.

"Did you aim to poison these two people?"

"No," came the soft reply. "It was just... good luck."

Draco looked away at this, not able to see how on earth Blaise could call such an act 'good luck'. Snape continued the questions, calm and unruffled as always. "Why did you do it?"

Blaise looked rather placid at this, just staring straight forwards, his mouth seemingly talking of its own accord. "My master told me to cause havoc at Hogwarts. And I did. He wants Dumbledore to break. He wants Potter to break. He told me to destroy the school from the inside, however I could manage it... and I have." A horrible, sickeningly calm smile curled his lips. "She is going to die. And my master will be pleased. I always hoped she would be the one to die... her, or Potter, or Malfoy... they are the ones that my master needs gone. Potter continues to unknowingly foil his plans. Malfoy is a danger... he knows much about my master. From his dead father. And my sister knew almost as much as Malfoy. And I have killed her for the Dark Lord."

"She isn't dead yet," said Draco, quietly.

"She shall be soon," said Blaise, tonelessly, though the glee in his eyes was all too obvious. "And then Potter will be vulnerable. The Dark Lord knows that there is something to do with Potter which stops him in his tracks... though he does not know. Nobody does. The Prophecy was broken. My lord shall have Potter killed. He cannot escape forever. And when Potter falls, so shall Dumbledore, and the rest of the wizarding world."

"Do you speak with the Dark Lord himself?" said Snape, calmly.

"Yes," said Blaise. Another flicker went across his eyes. "He talks to me often."

"Have you been marked?"

"Yes."

"Where?"

"The base of my spine," said Blaise, quietly. "It is the least noticable place. He no longer marks his Death Eaters on the forearm. It is one last attempt at having them undetected by the ministry... the fools only test for the mark on the arm."

Dumbledore stepped forward from the shadows. He looked remarkably grave, the lines on his face highlighting his great age, as the fire washed over his skin, making his beard gleam in the light. "Blaise... why would such a boy as you want to do such a service for the Dark Lord? Do you not feel any guilt or sadness for your sister?"

"No," came the firm reply. Blaise's eyes narrowed a little as his unfocused gaze in the fire turned far more angry. "For all my life, she has been the older. The stronger. The faster. The more sociable. My parents were so proud. But she had to go. She was nothing but trouble to us all. And it is the same with Malfoy... he was always the head of Slytherin. The pride of the house. The perfect Slytherin. But now, it is me..." he breathed. His eyes lit up with a mad, maniacal glint of power. "I am the perfect Slytherin. I am ambitious, cunning. Pureblooded. The Dark Lord himself says so. He will reward me for my troubles. And the ministry cannot stop me. They shall send me to Azkaban for my crimes... but I can escape. Azkaban was only a threat to me with the dementors, but there are now on the Dark Lord's side, along with the giants and the Heliopaths. My master is unstoppable. The wizarding world will fall."

"Enough," said Snape, so suddenly that Draco jumped. He turned to Dumbledore. "We need to alert the ministry... no doubt Fudge will want to come bustling here again with reporters in tow. Zabini is out of his mind, Headmaster."

Dumbledore paused for a moment, and then nodded, ever so slightly. "Yes... I'll send a message to Cornelius immediately. Draco? You could probably go and tell Harry what has happened... I'm sure he'll want to know that the culprit has been caught and has confessed."

Draco stood up, nodding and feeling rather numb by now. He didn't even really register that he had opened the door of Dumbledore's office, and been carried down by the revolving staircase, or even when he made his way down the corridor. His mind was full of that horrible look in Blaise's eye, as the boy had called himself the perfect Slytherin, and spoken of how Voldemort would reward him. At thinking the name, Draco felt a twinge in his lower back, just to one side of his spine. He cringed a little and put his hand over it. Being on heat was bad enough, but now he had a new, and far more sinister pain, to add to his discomfort.

He found himself in front of the doors to the hospital wing, and eased them open, creeping inside. Madam Pomfrey wasn't around - luckily. The matron had never really liked Draco much. She always rolled her eyes when he came into the hospital wing, and rather scathingly asked him how long he planned to be crippled for this time.

Harry was still awake in his bed, propped up against the pillows and reading a book quietly. Draco still couldn't get used to seeing Harry this way. So quiet and innocent, just sitting and thinking, reading with a curiously child-like expression on his face. As Draco entered the ward, Harry looked up from his book, and smiled ever so slightly. "Hi."

"Hi," said Draco. He sat down next to Harry's bed. "We got him."

"What?"

"We got him... Zabini. I was sent to hide by the lake, and he came. He's just confessed in Dumbledore's office, they're bringing the ministry of magic now." Draco sat back, scraping his hair vaguely off his face with splayed fingertips. His hair had once been his pride and joy, trimmed regularly, but it was now greasy and lank, and grown down around his shoulders.

Harry nodded, quietly, his eyes turning down to look into the bed sheets. "So it was definitely Blaise then?"

"Yes," said Draco. He waited a moment for this news to sink in, then went on. "We got a full confession... he's been marked as well."

"Marked?" Harry asked, raising an eyebrow.

Draco went on. "Tattooed with the Dark Mark. Marked is a sort of slang term. Blaise has got the mark at the base of his spine, from what he told us. He was under veritaserum too."

Harry looked as though he was trying to decide something for a moment, and then he asked, quietly, "Did he say what he felt about... about Kainda?"

"Yes..." Draco nodded, and it was very hard to look into those bright green eyes and say what he did. "He said it was just good luck... I don't think they were the closest family." Seeing the expression on Harry's face, Draco patted him, just once, on the shoulder.

"I'm okay..." said Harry, quietly, wiping a single hand across his eyes. "So... he really didn't care... he doesn't care that she's dying..."

"He... he seemed proud of it," said Draco. "He's vile... just vile... even by Death Eater standards."

"All Death Eaters are vile," said Harry, so suddenly that Draco found himself mildly taken aback. Silence followed this statement for a few moments, before Draco spoke again.

"You think so?" he said, calmly, raising one eyebrow. Harry nodded simply. Draco paused again, and then went on, in a calm, matter-of-fact sort of tone. "My father?"

Harry said nothing at this. Draco didn't really need him to. The look on his face said it all. After a moment of silence or so, Harry said, "Your father was... well... yes, it was tragic for you and your family, and I know that... but... well, he wasn't exactly angelic."

Draco smiled bemusedly at this, sitting back in his chair and curling up, catlike. "Yes, I know... the only thing that stops you thinking of him as a good man is the fact that he was a Death Eater, yes?"

"Well... yeah," said Harry. "It's just that... I saw him, in the graveyard. Wearing a hood. It's hard to forget something like that."

"I understand," said Draco. He checked his nails for a moment, and then said, casually, "How about Professor Snape?"

"Snape's not a Death Eater," said Harry, brushing this aside, calmly. "Well... yes, he is. Or he was. But he changed, he's not a proper Death Eater. He doesn't enjoy what he does."

Draco nodded at this. It made sort of sense. He thought about the whole thing for a moment, considering Harry, and then he said, quietly, "And what about me?"

Harry practically waved this aside. "You aren't a Death Eater..."

"Oh? Am I not?"

Harry's eyes flickered to him. Draco smiled at the expression on his face, surveying Harry for a moment more, and then explaining.

"Don't worry... I'm not about to try and strangle you or anything... I'm not working for the Dark Lord."

"But - you said..." Harry began, worriedly.

Draco nodded sombrely, and paused for a moment, still considering Harry. He decided to tell. "I'm more or less in Professor Snape's group... 'was' a Death Eater. Now reformed."

He saw Harry's eyes widen, and his jaw fall. "But... you can't be! You're only sixteen, and you haven't got the Dark Mark! I've seen your arms when you're getting changed for Quidditch!"

"Oh, my mark isn't on my arms..." said Draco. "It never is anymore. Anybody who's been marked recently has it placed somewhere discreet. Like me."

Harry was dying to ask, and Draco could see it in his eyes. Deciding to just show without making Harry ask the question, he stood up, and turned half on his side, to look at Harry over his shoulder. He shrugged his robes off, and then carefully, just lifted the hem of his shirt. And there it was. Burnt into his pale skin, glowing black, the Dark Mark, a skull with a serpent twisting out of its mouth. Draco saw Harry recoil backwards. "It's black," the Gryffindor said, a definite note of panic in his voice.

Draco nodded. Harry must know that a blackened Dark Mark meant only one thing. "Mmm... it turned a few days ago... he's calling the Death Eaters to him."

"Why?" said Harry, quietly, nervously.

Draco let his shirt drop again, tucking it down out of sight. "I don't know... Professor Snape's has turned too. All we can do now is wait to find out what it is that he wants."

"He's going to be angry that you didn't go to him," said Harry. "He'll come and find you, you know."

Draco nodded, with a rather heavy sigh. "Mmm... I have the feeling it's not just me he'll be coming for though."

He was going to continue, and try and soothe the frightened look on Harry's face, but at that moment, Madam Pomfrey came bustling out of her office, tidying her robes. "Malfoy!" she said. "What are you doing in here? These are not visiting hours!"

"I was just - " he began, but she cut across him.

"No! You were just nothing, go on! Out! You can come back at a reasonable time, not now, the sun isn't even up yet! Come on, out!"

And with that, she bustled him out of the room, practically prodding him to get him to move faster. Draco glanced over his shoulder just before she slammed the door in his face, and saw Harry looking back at him, deep in thought, worry still apparent on his face.