Harry knocked on the door. Gregory cracked it open, glanced at him, then opened the door just wide enough for Harry to slip through.

The room, off the hallway between the entrance to Slytherin House and the commons, felt spacious. Not as large as Harry's trunk, but almost as large as the room his trunk sat in last year, with the rest of the Ravenclaw first year boys. There were three relatively spartan beds, one along the far wall and one each on the left and right. To the right of the far bed Draco sat at his desk, back to the door, writing furiously. Stairs leading down into a small pool of water to the bed's left. Harry wondered if it connected to the pond he passed on the way in.

Gregory walked over to his desk and half-leaned against, half sat on his hands. After a few final notes, Draco firmly shut the small black book, and gently pushed it against the black lacquered cane resting in the crack between desk and wall.

"Hello Harry," Draco said as he stood up. "Sorry, eventful evening."

Harry nodded towards the pool. The torches (torches! Finally!) on the wall provided ample light to play across the small waves that lapped against the top stair, but never seemed to escape past it. "Aren't you worried something may come out of the water?"

"Not really," Draco said. "Alceriato!" The water bubbled noisily, but still never spilled out of the pool. Even inches away from the edge the floor stood bone dry. "It's uncomfortably warm even for a magician. A merman, well..." he shrugged. "Tepidius!" The bubbling faded as the enchantment ended. "In any case it's also an escape route."

Gregory angled his head towards the door, an inquiring look. Draco ignored it and sprawled out on his bed and stared up at the ceiling. "What say you, Gregory? Should we offer Crabbe's bunk to Potter?"

"I don't know, I'd have to think about it. You snore, Potter?"

Draco's tone had been playful, but experience left Gregory no doubt as to the intent. Draco wanted Gregory's opinion, he had doubts.

"I suppose there are upsides," Gregory said noncommittally. Gregory thought that it would be exciting to have Harry Potter for a room-mate, and possibly useful. But Gregory had seen, second hand, the toll that Harry's friendship had put on Draco.

"I didn't mean to impose. In Ravenclaw each year has a room," said Harry.

"Oh, you know very well that's how it works here, too, Potter." Draco waved his hands towards the commons area. "Gregory and I will be summarily booted back there in a week or two, no doubt. So it doesn't cost me anything to be make the offer." Gregory chuckled.

Harry sat down on what he now considered his bed. "Was the duel that important?"

Draco sat up and looked at him, then shoved his back against the wall and drew his feet up against his chest. "That? Not really, which is why I could concede so quickly. That was but a symptom of the reduced status of House Malfoy."

"Then why Strategema with Ethan," Harry asked. Seeing puzzled looks, he explained. "From a Muggle show. A master player frustrates another master by making inferior moves during their game. He ignores superior moves to play for the draw. Which infuriates his opponent."

Draco shook his head. "Nothing so clever. The Duel gave me an opening. A chance to confirm that people could trust me. Could back me, without appearing weak." Draco rested his knees on his chin. "Trust is a rare commodity, here. Ethan handed me a bottle full of it and I decided how to play it, without considering him. And you know the worst part? I'd warned myself against that type of mistake earlier today"

"Well, you got to state your case."

Draco turned slightly towards Gregory, who shook his head.

"Nobody will remember that tomorrow. They've probably forgotten already. If we had people reinforcing our position, restating it..." Gregory trailed off. Potter could figure it out.

Draco sighed. "Every strength has a corresponding weakness."

Harry interrupted. "And vice versa, like using truth serum to your benefit, Draco. That was a good idea."

Draco bit his lip. "Thinking logically helps you, but blinds you to how others think. You can work it out, but it takes time. I'm wondering if it's blinding me, too." He pulled his knees closer.

Harry Potter had seen Draco in a variety of moods before, but morose was new experience.

"I suppose it does. No, I know it does. Its one of those cases where I want to believe people will work things out, despite all the evidence I have from last year. But I have a friend with a masterful understanding of human nature."

Draco snorted. "He's talking about you, Gregory."

"Obviously."

From the noise in the common room it sounded like the prefect had ordered the first years up to their room, the room that Draco had never set foot in all last year.

"Is it really that bad, Draco?"

"I don't know. Imagine how Robert feels, knowing Ethan didn't answer quickly. I had to resign, right away, before he answered. That doesn't even get into Ethan and Sara. I should have never made that accusation." Draco shuffled over to his dresser and started to put away his cloak, to prepare his bed. "And the part that I never considered, was how much I'd been lying to myself. That shook me."

"People lie to themselves all the time, Draco" said Harry.

"Not consciously," said Gregory. "The … awareness of it, that's novel. We could see it, we all saw Draco trying to answer and not being able to." Harry Potter had never seen this side of Gregory (or Vincent, he remembered) and realized that of course Draco Malfoy shared an easy camaraderie with his friends. With a shock Harry Potter remembered Gregory's long pause under the Sorting Hat. At the time, he'd naturally assumed the choice was between Hufflepuff and Slytherin. Now Ravenclaw seemed likely. Lord Malfoy dare not share his secrets with fools, nor would he want fools helping his children.

Gregory's public silence showed that he understood his role. And nothing more.

Harry Potter stood in a room with Draco's consigliere. One of them, anyway. The memory of Lucius with the Elder Goyle and Crabbe, their unspoken coordination, flash to mind. That kind of trust required years. Perhaps generations.

Harry reconsidered if living with Draco would be a good idea, and tried to remember exactly how he'd been invited. Just how detailed a message could they exchange under my nose?

Draco sighed. "Every. Single. Witch. Has probably heard about this by now."

Harry suspected some heard it hours ago. "I should, uh, go get my trunk. I'll be back in a bit."

"Do you need any help?" Gregory and Draco asked simultaneously.

"No, I'm fine." Harry stopped at the door. "Well, there's one thing, at least. I think Salazar Slytherin would approve of this tradition. Who knows? Those duels may date back to Slytherin himself."

"What makes you say that?" Gregory asked, while Draco said "Not that I've heard of."

Harry definitely saw them exchange a look that had meaning he couldn't read.

"Maybe I should find another place to stay," said Harry. "I mean, I think I'd be intruding."

"No, I think you should stay, Potter," said Draco. "But if you do we can't go tip-toeing around like this. I've kept your secrets mostly, from Vincent and Gregory. But if you move in we don't exclude Gregory. You'd be here with both of us. Everything I'm in. I've told him my side already, but … we built up our relation by sharing secrets. This won't work if we all have to spend minutes thinking about what to say."

Harry turned to Gregory. "So, when you said there were upsides..."

"Better to have you inside pissing out, Potter. I live with Draco in any case, I'd like to understand how you spin him around. And since we're all working to save the House" – now Harry shot Draco a look, one that Gregory read easily as 'I suppose fair's fair, but still...' – "it will make all our lives easier."

"So, to confirm, the two of you are inviting me to live here?"

"Until such time as we get booted back to the 2nd year floor," said Gregory, and thrust out his hand.

Harry shook it. "I've got to get my stuff." Gregory held firm.

"So, what did you mean, about Salazar?" asked Gregory, releasing the hand. "What do you know about Slytherin that we don't?"

Harry Potter stood there, thinking.

But he wasn't the only one.

Harry Potter thought faster than most students, faster than most adults even, and he thought faster (and in some ways, deeper) than Draco Malfoy. But he didn't think orders of magnitude faster. Harry Potter quickly considered the implications of revealing his secret to Gregory, whom he didn't know well, and to Draco, who would realize the implication eventually.

But most of Harry Potter's legendary speed came from the fact that he thought ahead. Harry planned for routine trouble and spent time considering trouble most people wouldn't think about. From Harry's point of view, being surprised at his speed of thought was about as useful as being surprised that a Grandmaster could defeat dozens of players simultaneously with almost no effort.

While the Master's opponents stared at the chessboard at move 10, the Grandmaster recognized this game and knew the best move for each response. Grandmasters, as part of their journey, literally wrote books about standard positions. Not only did a Master (of any endeavour) think more clearly and deeply than a novice, in most cases he didn't have to think at all. Certainly not against lesser players. Becoming world class meant outpreparing most opponent, and only out-thinking the truly worthy. Harry Potter's thought ahead about battles, gambits to get or hide information, reacting in the face of disasters. He'd trained himself how to think.

In a novel situation Harry Potter could find a great move, a clever move. But he hadn't prepared one for this.

Harry Potter had wandered into a game half played because he'd tried to cheer up Draco without thinking about it and because he'd been so struck by the symmetry of Draco's Duel and his own experiences (in all respects except for the stakes) that he'd just blurted out his cheerful message. So, for the first time in several days, Harry Potter analyzed a novel position – whether to tell Draco and Gregory.

Harry Potter understood his mistake in making the offhand comment as soon as Gregory asked the question. So, he'd started to think a few seconds before Draco did. But he wasted those few seconds hoping that in in a few years he'd move past these simple mistakes to make more interesting and complex mistakes. And deciding that he didn't fault himself for having tried to cheer up Draco. So, once again, Harry Potter had jumped the starters gun when out-plotting those around him.

But Draco didn't have to think, just remember. A Green-and-Silver lettered day from last year sprang instantly to mind. Draco recognized a mate in one. His only decision: speak or stay silent.

On a normal day Draco Malfoy would have stayed silent. Silence, perhaps masked by meaningless chatter, was usually the prudent course. Silence revealed little. But today Draco felt ambushed by fate and, as so often happens, a player who just blundered away one piece often stops thinking and plays the next obvious move. Or is so relieved to spot a potentially good move that they play first, analyze later (if at all).

But mostly Draco felt annoyed that Harry lacked the courtesy to keep up small talk or try to deflect the conversation while he thought. That insult, more than any calculation, led Draco's revelation.

"Potter's the Heir of Slytherin, Gregory." Gregory's eyes bugged out, then narrowed. Harry Potter turned, took out his wand and cast several wards on the door, then sat on what all three boys now considered his bed.

"I'm not the Heir. But I am Parselmouth. Draco discovered it actually. It's not the sort of thing I'd tell anyone, even Draco. That's why I was thinking. It's not that I don't trust you to keep my secrets. But a lot of people would react ... poorly if I told them. Anyway, Draco was around when it happened. To me it just sounded like English. But Draco couldn't understand it and I'd never even heard of a Parselmouth."

Gregory, more so than either of the other two boys in the room, was in a totally unexpected situation, so it was Draco who interrupted.

"That doesn't really clear it up."

"You can't lie in Parseltongue. It's not quite the same as the serum, I think. It's like two drops, but you can stay silent. But if you speak, you say the truth."

"And what happens if you say something that you don't know is a lie? Do you state the correct information?"

"I don't know, Draco. I don't think so. Almost certainly not" If Parseltongue revealed truths unknown to the speaker, Voldemort would have certainly discovered he had an infallible Oracle. Harry felt practically certain that Parseltongue, like Veritaserum, relied on the subject's state of mind. He'd decided this as Draco walked to his desk and took out a scroll.

"Let's experiment. I don't suppose you know many spells about repairing garments? No? Well, I'll tell you about three of them, one of which is incorrect, and then you say it in Parseltongue … if one of the descriptions changes, then we'll know."

Harry considered the experimental protocols, even though he considered it a forgone conclusion. "If Gregory knows which one is a lie then he shouldn't be visible to me, Draco. I might be able to get a clue from that. It's called the Clever Hans effect..." Harry Potter went on to describe correct experimental protocols at some length, being sure to clarify points for Gregory that Draco already knew.

The experiment proved it. You couldn't knowingly lie in Parseltongue. Harry confirmed that he said "There is a 2/3rd probability that this spell works as follows," because of the information he knew. Once Draco revealed that Percaxia actually cleaned, folded and pressed clothes (and did not fix frayed hems, as he'd written down), then Harry could no longer describe it as a twice likely as not clothess mending sspell, which he'd been able to do earlier and caveats disappeared for the other two descriptions.

Later that night, staring up at the ceiling as Harry and Gregory slept, Draco mentally berated himself. He reviewed that day's mistakes, how the cascading failures piled up. He'd done well, in many regards. He'd seized opportunities and forged ahead. But … but …. Draco couldn't sleep, and rather than toss and turn and fight his insomnia he put his time to use and reviewed the day. He mentally made notes.

Some mistakes he'd only noticed later in the clarity of the night, to the sound of Gregory's snoring.

Draco Malfoy understood his biggest mistake hours earlier. In fact, only several heartbeats after revealing Potter's secret Draco realized the enormity of his mistake. Years later, after he had a more adult control over his emotions, that mistake would be the one that woke him up at night – Revealing his understanding instead of saying silent and thinking things through first.

Like Potter had been trying to do.

The slim comfort Draco took was that he'd at least carried on his conversation as if nothing had happened. He'd avoided the exact same mistake Potter had been making. He hadn't stayed silent (or worse, gasped dramatically) to reveal his thoughts. He'd quickly changed the subject, and changed it well.

He'd offered Harry an experiment.

Draco had no idea if it distracted Harry. Probably not, but Professor Quirrell taught when your only hope is slim you still take it. Draco had no illusions. Harry Potter was neither God nor Monster; legends had already grown around him but Potter wasn't omniscient, just infuriatingly clever. And, like Draco, Harry's youth left him prone to mistakes.

Draco wondered if he underestimated Potter (Harry complained about that often enough). But he'd sometimes overestimated Potter.

More so than anyone else (that he knew), Draco Malfoy had observed Potter up close, had seen his thought processes. He'd seen Harry's powers, magical and non. He'd tried, to the best of his ability, to sort truth from fiction about Harry Potter. Months ago, his intuition told him that Harry Potter defeated Voldemort. He had no evidence. He could think of no experiment. Draco used the old ways of plotting: he assembled facts, gathered information, and thought. He reviewed them again and again that night.

* Harry's Patronus was brilliant and blinding.

* His knowledge of that spell was profound. He'd taught Draco; He'd known Draco could learn it, a fact that surprised Draco and would stun most Slytherins.

* Harry wouldn't reveal his Patronus directly. It contained a secret Potter made an effort to keep hidden.

* According to everyone, Harry Potter terrified a Dementor at Hermione's trial.

* … without even summoning a Patronus.

* Granger's death drove Potter relentlessly.

* He clearly cared for her deeply; more than Draco, possibly more than anyone else.

* Hermione Granger came back from the dead at the same time that Voldemort - her presumed killer - died.

* Hermione Granger could destroy Dementors. She'd destroyed them all, at Azkaban.

Draco had listed those clues over the summer. These facts marked Harry Potter, his friend and rival, as the sort of person who would always outshine him. But also as the boy who avenged Father's death.

He couldn't prove it. He'd probably never have proof. Harry, despite his boyish blunders, would never reveal the fact to anyone he was not completely sure of.

Draco agonized countless hours, wondering if Potter could have prevented Father's death, could have been more clever. Draco didn't know, been afraid to ask. Been afraid of how he might act. Since Draco couldn't trust his own reaction to the news he could hardly blame Harry for being unsure. Harry would never tell him. For friendship, perhaps, but for his own reasons.

Draco knew all of this. He'd pieced it together over the summer, along with his understanding that Father knew he was going to his death that June night.

Draco glanced at the cane on his desk, silver snake head placed so Draco could see it from his bed. The cane Father carried constantly, the Sigil of House Malfoy handed down across centuries. Draco had unlocked some of its secrets, his diary had revealed others. His other birthright.

The cane Draco discovered that night leaning by Father's chair.

A sign, sure as any letter, that Father suspected. His farewell to Draco. Perhaps he'd always left it at home, years ago, when he dealt with Voldemort. Perhaps he feared Voldemort might not restrain himself, might challenge his power against the weight of House Malfoy. Perhaps he could not conceal it, dare not risk anyone spotting it. How often had he left it there? Just in case... so his beloved Narcissa could pass it down to his infant son. Or maybe he'd discovered some dread secret and went knowingly this one time, to protect Draco. Draco didn't know. The game of subtleties had limits. He'd lost the summer wondering.

Could Potter have saved Father? In that regard, Draco felt comforted by his months of reflection. It seemed unlikely. Even if Potter had been there with the Death Eaters, it would be ludicrous to assume he could deal with them and Voldemort. Six hours ago Draco Malfoy trusted Harry Potter, mostly. If he'd been under Veritaserum Draco Malfoy would feel compelled to use a heavily footnoted definition of 'trust' that would cement his reputation for deviousness, terrify Hufflepuffs, and make Potter proud over the sheer precision and deep implications.

Three hours after midnight on the first day of school, Draco Malfoy lay awake agonizing over the new fact (not proven, but probable) he'd added to his list.

Harry Potter chatted with Voldemort before he killed him.

Now, with the moonlight's reflection bathing the commandeered room in a silvery glow, Draco's list of facts about Harry Potter looked alarming.

Author's Note - This ends the prologue.