“So, my boy, are you excited?” Dumbledore said with a smile as he leaned back in his chair and clasped his hands on his abdomen.

“Sorry, sir?” Harry said, confused about what the man could be referring to. There wasn’t much to be excited about, not anymore.

“Professor Slughorn’s Christmas party. I heard you got an invitation,” Dumbledore said. “I am not surprised. He is drawn to special students, like yourself.”

“Yeah, I’ve noticed,” Harry said, still somewhat bitter about singled out as 'special' because of his past. “And, sure, it should be fun.”

“Yes, Horace has always thrown excellent parties,” Dumbledore said. “Have you found a friend to accompany you?”

“Uh, yeah, I asked Luna Lovegood.”

He had managed to talk to Luna again in the library away from prying eyes a few days after their incident outside the Great Hall. He was originally going to bring Hermione, but Slughorn ended up inviting her as well, likely for being dubbed the ‘brightest witch of her age’ despite being Muggleborn. She had invited Ron so he was included and Harry had quickly decided on Luna, who ended up being ecstatic at the invitation. Harry assumed it was because she was never invited anywhere or included in anything by her housemates or anyone else for that matter. No one seemed to appreciate the amazing friend they could have in Luna.

“A wonderful choice. A lovely young lady,” Dumbledore said. “It is actually very fortunate that you have caught Professor’s Slughorn’s attention for he is the subject of the memory you will see tonight. This memory is the reason I convinced Professor Slughorn to return to Hogwarts.”

Harry was curious how Slughorn could be connected to Voldemort. The man seemed as far from the Dark Arts as he possibly could be. He approached the Pensieve as Dumbledore did, watching the memory drip into the basin.

“Many years ago, Professor Slughorn was one of Tom’s professors here at Hogwarts. Like you, Professor Slughorn recognized Tom as a special student. The two appeared to become close until something happened between them, something that showed what Tom would become. There is something important about this memory, but I will explain after.”

Harry nodded and entered the memory, landing in what he recognized to be the Potions professor’s office. It looked nothing like it did when Snape occupied it. It had a warm atmosphere with books lining shelves and a fire roaring in the fireplace. A large round table was sat in the center of the office, occupied by several people, including a younger Slughorn and a sixteen-year-old Tom Riddle. Some of the other students at the table were chattering with each other quietly while Slughorn was in the process of opening a gift.

It was then Harry noticed that the memory seemed to have a haze over it, making everything just a touch dimmer and fuzzier. He wondered what it was as none of the other memories were like that. He assumed it was what Dumbledore would explain after, so he did his best to ignore it and watch the memory play out.

“Ah, how wonderful, my dear boy. Candied pineapple, my favourite,” Slughorn said happily, smiling widely. “Thank you, Tom, very much.”

Tom inclined his head with his own smile. “You’re very welcome, sir. A show of my appreciation for your kindness.”

“Such a dear boy you are,” Slughorn praised affectionately with a chuckle.

“So, is it true, sir?” Tom asked casually. “Is Professor Merrythought retiring?”

“Merlin’s beard, Tom, how do you do it? You seem to know everything, many things you ought not to know,” Slughorn said. He seemed surprised and slightly exasperated with Tom, but not angry.

“I’m curious and enjoy investigating things that pique my interest,” Tom said and Harry noticed a familiar glint in the dark eyes.

“You best be careful you don’t get yourself into trouble one day, Tom. Some things in this world are not meant to be known,” Slughorn said.

Tom opened his mouth to respond, but they never heard what he said. Harry was startled when a thick, grey fog blanketed the memory, nearly hiding it from view. He jumped slightly when Slughorn’s voice boomed from the fog.

“There’s something wrong in you, boy, and, one day, everyone will see it! Just you wait!”

Harry frowned at the tone and hateful words. They didn’t match Slughorn or the conversation. Sure, Slughorn had been giving Tom a warning, but it had still been a friendly warning. The fog disappeared and the scene had changed slightly. Only Slughorn and Tom remained at the table now.

“Quite the group of friends you’ve made, Tom,” Slughorn said as he popped a piece of candied pineapple in his mouth.

Tom shrugged. “Really just acquaintances,” he said dismissively. “Everyone needs followers, don’t you think so, Professor?”

Harry frowned again at Tom’s cockiness and that glint that flashed in his eye again. Slughorn appeared uncomfortable with Tom’s comment as he stuttered, trying to find something to say.

“Professor,” Tom said, saving Slughorn from the awkward moment. “I would wager you are one of the most knowledgeable wizards I know.”

Slughorn blushed and Harry was impressed at Tom’s ability to manipulate the man. He supposed manipulation was a skill Tom had to have in order to successfully create the Death Eaters.

“I’ve discovered an interesting area of magic and I hoped you could tell me more,” Tom said.

“Well, yes, if I can, of course,” Slughorn agreed.

“I stumbled upon it in the Restricted Section of the library,” Tom said and glanced at Slughorn with a half-smirk that made Harry tense. It reminded him a lot of the Voldemort he knew. “Horcruxes, I believe was the term.”

Slughorn blanched and went to respond, but then the fog from before returned. Once again, Slughorn’s voice boomed from the fog, even louder this time.

“How dare you ask me about such evil! Even if I knew anything, I wouldn’t tell you! Get out! Never ask me about that ever again! Out! OUT!”

Harry blinked as he suddenly found himself back in Dumbledore’s office. What had he just seen? It had been the strangest memory ever. He quickly sat, hoping it would encourage Dumbledore to explain faster as he stared expectantly at the man.

“I trust you noticed differences with this memory,” Dumbledore said.

Harry nodded. “It was all hazy and then the weird fog.”

“Yes. I believe this to be a fake memory that has been tampered with.”

“That’s possible?”

“Indeed. I believe Professor Slughorn has hidden his true response to Tom’s inquiry, perhaps out of shame,” Dumbledore said seriously. “I believe the key to Voldemort becoming what he is today is hidden within Professor Slughorn’s true memory of this night.”

“You mean the horcruxes? Why, what is that?” Harry asked, having never heard of anything like it before.

“I will have to save that explanation for after we retrieve the real memory.”

Harry frowned, disappointed. It felt like something he should really know. “Okay, but how are we going to get the memory?”

“That is where you come in,” Dumbledore said. “Professor Slughorn has taken a liking to you and I believe you can convince him to give up the real memory.”

“Me? But, how am I supposed to do that?”

“However you decide,” Dumbledore said. “It will be difficult. He is quite a powerful Occlumens and I believe he has buried the memory deep inside his mind.”

Harry sat back, a little overwhelmed. How was he supposed to get Slughorn to spill his deepest, darkest secret? Slughorn liked him, sure, but he didn’t know the man that well.

“Can I put my faith in you to succeed?” Dumbledore said, gazing at Harry intently. “This could very well be the final piece of the puzzle needed to defeat Voldemort.”

Harry swallowed thickly at the pressure.

“You must not fail me, Harry.”

Harry’s stomach tightened. “Yes, sir. I promise I’ll get the memory no matter what.”

Dumbledore gave him a gentle smile, his eye sparkling. “That’s my boy. That is all for tonight. However, I ask you do not mention the horcruxes to your friends.”

Harry nodded in agreement though he couldn’t help but wonder why.

“Very good. Off you go now.”

“Yes, sir. Good night.”

Harry smiled as Luna danced in her odd way with Ron awkwardly shuffling with her. Ron obviously didn’t want to dance and still thought Luna to be strange, but his big-brother-to-a-little-sister identity was kicking in and he wanted her to have fun. He moved his gaze to Hermione who was sitting in a couple chairs off to the side, engaged in an intense conversation with one of the other invitees, a Hufflepuff boy. Harry honestly couldn’t remember who he was or what made him special to Slughorn.

Dinner had been Slughorn’s chance to ask questions and make his guests reveal their personal or familial accomplishments. Some students were more than happy to brag, but most were uncomfortable. Harry had been so relieved when dinner ended before Slughorn could get to him.

They had all moved to the next room with its wonderfully bright and sparkling decorations, floating silver candles above their heads. Other students had been employed for the evening as servers, walking around with trays of beverages and post-dinner appetizers to offer the guests.

As he looked around, he was honestly glad he had attended, and not just for the opportunity to speak with Slughorn. The party had not been as bad as he anticipated and had actually been fun. It had been a nice distraction and a nice thing to do with his friends rather than sitting around, pondering the death and destruction of Hogwarts and the wizarding world. It was refreshing to see his friends happy, at least for a night, for the first time in years.

“Harry, dear boy, I hope you are enjoying yourself,” Slughorn said as he came to stand with Harry, a drink in his hand.

“I am, sir, thank you for the invitation,” Harry said, smiling.

“Excellent, excellent,” Slughorn said. “I am sorry we did not get to you at dinner.”

“Not to worry, sir. Everyone already knows my story anyway.”

“Indeed they do,” Slughorn chuckled.

They were quiet for a time, watching the others chat, laugh, and dance. He could almost forget they were even in Hogwarts with the light atmosphere of the party, an emotion not felt all year. After some time, Harry decided to brooch the subject on his mind.

“Professor?” Harry said, regaining the man’s attention. “Can I ask you about something?”

“Of course, dear boy, anything.”

“Correct me if I’m wrong, but would I be correct in assuming you knew my mother, Lily?”

Slughorn’s expression softened, saddened, but his eyes glistened with memory and affection. “Yes, I knew her. Quite well, I might add. I was her Potions professor throughout her time at Hogwarts. An amazing witch she was. So bright and talented and kind. A beautiful heart in a beautiful young girl.”

Harry’s heart ached for the woman he never knew, but so many others did yet they never spoke of her. He heard about James often, but never Lily.

“Your Miss Granger is very much like Lily,” Slughorn added, making Harry smile at his friend. “Lily was particularly skilled at Charms, though she excelled in all her classes, including Potions. She was a member of the Slug Club because of her impressive skill. In my class, she was always competing for the top spot with her friend, Severus.”

Harry started for a moment at the mention of Snape. He and his mother had been friends? He remembered the memory he had seen last year and knew they had known each other, but Snape had been awful to her. How had they been friends?

“She gave me a gift once,” Slughorn said, clearly caught up in his memories. “A little fish in a fishbowl. I had that fish for many years, but, one day, it was just gone and a white lily was floating on top of the bowl instead. It was the day she died.”

Harry felt his eyes sting and watched Slughorn turn to him, tears in his own eyes.

“I regret that you did not get to know her,” Slughorn whispered, “but you have a lot of her in you. I can see it.”

Harry smiled, sadly this time, but also grateful at finally hearing he was like his mother. He only ever heard about having her eyes, but being like his father.

“Thank you, sir,” Harry said quietly.

They fell quiet again, each remembering Lily Potter. Harry eventually turned his thoughts to Dumbledore and the memory from last night and Tom Riddle. Now was a perfect time to make his first attempt at retrieving Slughorn’s real memory.

“Professor, were you teaching here when Tom Riddle was a student?” Harry asked as casually as possible.

Slughorn visibly tensed. He was quiet, obviously deciding what he wanted to say. “Yes, I taught Tom.”

“Can you tell me about him, what he was like?” Harry asked.

Slughorn hesitated.

“I just want to know more about the man who killed my parents. Maybe find a reason why, why they had to die,” Harry said, almost pleading as some of the desperation he’d felt his whole life bled into his words.

Slughorn took a deep breath. Harry thought the man looked sad and he wondered why.

“Tom was…something else,” Slughorn began. “He was also incredibly bright and talented. Even so young, he had amazing power.”

“What was he…interested in?”

“If you’re asking if he was interested in the Dark Arts even as a child, the answer is yes,” Slughorn said. “He was a hurt child, troubled and traumatized. It helped him feel more in control to have knowledge of the Dark Arts. It was very much just a desire for knowledge, not practice, at least, not until…” he trailed off and Harry knew he had to be thinking of that night.

“Until he learned about horcruxes?” Harry prodded. “He changed, didn’t he? He wanted to control people, hurt them.”

Slughorn cast him a frown. “Where did you hear that?”

“I mean, it’s easy to figure out,” Harry said. “Dumbledore told me how angry Tom was, how badly he wanted to master the Dark Arts. He manipulated others into following and worshipping him even in school. They were the early Death Eaters.”

Slughorn’s frowned deepened. “Tom was angry and he did become too consumed with the Dark Arts, but I do not believe he wanted to hurt people. Well, except his family,” Slughorn said. “I am also unsure where you heard that nonsense about early Death Eaters. Tom did not treat anyone that way. He just wanted friends.”

“But, he did ask you about horcruxes?”

“He did,” Slughorn said.

“Why did he want to know about them?”

“Something happened to him when he opened that Chamber. That’s what pushed him into the Dark Arts. Something in that Chamber affected him, changed him.”

“Professor, I need the memory about Tom asking about horcruxes, the real one. Please, sir, Dumbledore—”

“I think that’s enough of that topic for now, Mr. Potter,” Slughorn said and Harry frowned. The clock suddenly began to dong loudly, making the both of them jump. “Oh, look at the time. I believe it is time to call it a night. Have a good Christmas, Mr. Potter.”

Slughorn hurried off to dismiss and say goodbye to his other guests before Harry could say anything else. Harry furrowed his eyebrows, utterly confused at what Slughorn had said about Tom. Was he still hiding the truth, still ashamed, and had convinced himself of his lie? He was honestly skeptical, but it was the only thing that made sense because the only other explanation would be that Dumbledore was the one that had lied which wasn’t possible. He would just have to keep trying and convince Slughorn to face the truth.

He ignored the pit that had formed in his stomach and the strange electric pulse he felt in the air around him.

Harry followed Ron and Hermione up the Grand Staircase after breakfast on autopilot, unable to stop thinking about his conversation with Slughorn the previous night. There was something very off about how Slughorn seemed to remember Tom Riddle and how Dumbledore did. There didn’t seem to be any reason Dumbledore would lie, so it had to be Slughorn. The professor had to be lying to hide whatever help he gave to Tom that allowed him to become Voldemort, something to do with horcruxes, whatever they were. As Dumbledore had requested, he hadn’t mentioned the horcrux term to Ron and Hermione, but he couldn’t help but want to. He had a strong feeling he needed to know what a horcrux was and he couldn’t understand why Dumbledore was keeping it from him.

He sighed and glanced down a corridor as they passed. He stopped abruptly, shocked at what he was seeing. Amongst the students racing around, a woman stood about halfway down the corridor in the middle of the hall. Everyone was oblivious to her presence, everyone except Harry. Why could only he see her?

As he stared, he realized, again with shock, that it was the woman from his dreams. She had a sad, withdrawn expression, but, as their eyes met, she began to smile.

He turned to Ron and Hermione to ask if they could see her, but found them looking at him with frowns. They clearly didn’t see her either.

“Is everything alright?” Hermione asked.

Harry looked back down the corridor to find the woman was gone. Had she actually been there?

“Harry?” Hermione said again, her voice worried.

“I…I thought I saw something,” Harry said, still staring intently down the hall in hopes the woman would reappear and prove he wasn’t insane.

“Another vision?” Hermione whispered as a student walked by.

Harry shook his head. “No, this was different than the visions. She was solid, like she was really there. The visions are almost foggy. Plus, no headache.”

“She?” Ron repeated.

“Yeah, I saw a woman,” Harry said. “It was the woman from my dreams.”

“Are you sure?” Hermione asked and Harry nodded. “Let’s go to the library instead. We haven’t found her yet. There’s still a chance she’s in there somewhere.”

“Sure, let’s go,” Harry said, casting another glance down the corridor before following his friends up the stairs to the next floor.

“She’s still never said anything?” Ron asked as they turned in direction of the library.

Harry shook his head. “She just stares. She usually looks sad even though she tries to smile.”

“We’ll keep looking until we find her,” Hermione said optimistically.

“Yeah,” Harry said absently. He wasn’t so sure of their search anymore. There was something strange about the woman and he had a feeling they wouldn’t find her in any history book.