We made it back to his house in about ten minutes. Alphys went up to Sans’s door. “S-Sans? Are you there?”

“no.”

“Sans, come out. Frisk told me to talk to you.”

“what did she say about me?”

“S-she said you snapped… and got really mad.”

Sans sighed. “i kind of figured…”

“S-sorry. D-do you want me to leave?”

“only if you want to….”

“B-but Frisk told me to talk to you. Please come out!”

“no.”

“Come on, Sans! What’s wrong with you? You’re never like this!”

“well, then apparently you don't know me very well.”

“Sans, if you don't come out, I'm going to get Undyne to break this door down!”

Sans opened the door. “welp, come inside… i guess…”

“Sans, what’s going on?” Alphys asked, sitting down on the chair in the corner.

“nothing…” Sans shut the door.

“Sans, obviously something is going on, or Frisk wouldn't have gotten me.”

“sure, you're right. now what else do you want?”

“I want you to tell me what exactly is going on here. “Frisk says you guys got attacked by Flowey and Chara. Is that even possible? And, Frisk told me that the Queen's dead.”

Sans's eyes turned black at the mention of the Queen’s death. “so what else do you want to know? it seems like the kid has already explained what happened to us.”

“I want to help. I also want you to explain what else is going on, and why you needed the dt extractor.”

“i want the dt extractor because i’m going to try to maybe separate chara from sarah and frisk. there. are you happy now?”

“Who’s Sarah? Anyway, how can I help?”

“sarah is frisk’s sister. anyway, if you really want to help that bad then you can prep the dt extractor.”

“On it. I'll just go get Undyne to go down there with me, and-” Sans cut her off.

“no. i don’t want anyone else going down there.”

“Okay then. Can Frisk come with at least? I really don't like going down there alone.”

“yeah, sure.”

“Before I go Sans… Please remember that you always have friends who can help you if you just ask.” She shut the door. “Frisk! Come on, I'm going to the lab.”

“Can Sarah come?” I asked Alphys.

“Uh, yeah…”

“Great! C’mon Sarah, let’s go!” We walked back down to the place where we had first watched the sun rise, then headed back into the underground, getting to the lab in a relatively short time. “So, what are we down here for?” I asked.

“U-um, I really think that Sans should tell you that…”

“Sans isn't here though.” I said. “You’re an adult, you should be qualified to tell me.” We were now in the elevator.

“W-well I-I…”

“C’mon. What could it have to do with me?” I asked, oblivious.

“Well yes… but hey! Here it is, just like I left it!” She said, stepping out of the elevator.

“What is that?” Sarah asked.

“The dt extractor?” I asked, confused. “What’s it for?”

“Hey, isn't it that one thing that guy made?” Sarah asked me. “What was his name again? Ga-”

“Sshhh!” I said, hoping Alphys just thought Sarah was crazy.

“Wait, who?” Alphys asked.

“No one.” I said, nudging Sarah to keep her mouth shut. It didn't work.

“We met some guy in Waterfall earlier. He said he was the royal scientist before you, and his name’s Gaster. How do you not know this?”

I did a facepalm, while Alphys stared in astonishment.

“The first royal scientist? But I… no…? Why can't I remember this?” Alphys asked with a puzzled look on her face.

“Alphys, i-it’s really nothing to worry about.” I said, a nervous smile on my face. I sent a quick glare at Sarah.

“N-no, I-I should remember this.” Alphys said, trying to sort through her memories. “Why can’t I remember?”

“Because.” I said. “It’s not… important?” I said, trying to come up with something.

“N-no, it’s obviously something important. The royal scientist before me? Come on, Alphys, think!” She said, hitting her hand against her head.

“What’s going on?” Sarah asked me.

“Something not good.” I replied. “They don't remember Gaster because he was erased from existence, and no one remembers him. Now Alphys is forcing herself to remember, and that is bad.”

“Wait, Sans told me something about no one remembering…” Sarah replied.

“You knew, and you still brought it up?!” I exclaimed.

“I didn't know it was bad.”

“Well, it is, and now I don't know what to do! I should go back and get Sans, but I'm not leaving Alphys, who might do something reckless if she’s alone, and I wouldn't leave you with her either, in case you said something else.”

“Oh, you guys can leave. I’ll be fine, I know what I'm doing.”

“Are you sure?” I asked. “Because sometimes… well…”

“Well what?” Alphys asked looking puzzled.

“You just sometimes… well, I’m worried you might do something, trying to remember, and no one will be down here to help.”

“You guys won't be long, right? I still need to prepare the dt extractor and that will take me a long time. So I probably won't have time for something like that.”

“Speaking of which, you never did tell me why you had to get it set up.” I said.

“If you're going to go see Sans, then he can tell you.”

“But-”

“No buts.” Alphys said, pushing them towards the elevator.

“Fine. I'll ask Sans. But if he doesn't tell me, will you?”

“O-okay, sure.” Alphys said as she pushed up her glasses.

We quickly went back up to the surface. “Sans.” I said, knocking on his room door. “I need to tell you something.”

“the door is unlocked.” Sans said through the door.

I opened it. “We have a problem.” I said to him, bracing myself for if he got mad again.

“yeah, about what?” Sans asked sitting on his bed.

“Sarah told Alphys about…”

“yeah?”

“About… Gaster.” I said nervously.

“oh, really now?”

“Y-yeah. And now Alphys is trying to remember him, down in the lab. It’s just a big mess.”

“i’m gonna have to have a meaningful conversation with sarah then.”

“Um, o-okay then. We should probably go back down there, so Alphys isn't alone.”

“okay. did sarah come with you?”

“Here? Yeah, she came with. Why?”

“no reason. anyway, do you want to go check on alphys now?”

“Yeah, but real quick, why do you need the dt extractor? Alphys wouldn't tell me.”

“we’re going to use it to get chara out of you.”

“H-how?” I asked nervously.

“we’re going to extract little bits of determination from you so we can weaken chara and separate her from your soul.”

“That doesn't sound very safe.” I said. “I mean, weakening my soul? Wouldn't that kill me?”

“theoretically it won't kill you. you do have a lot of determination, so i wouldn't be worried.”

“But, I don't have a high level of HP. Wouldn't that factor in at all?”

“just as long as you go in there with full hp you should be fine. if your soul gets too damaged then we'll pull you out.”

“Wait, my soul can get damaged?” I exclaimed. “Now it really doesn't sound safe.”

“yeah… there is a small possibility of your soul fracturing, but the probability is really small.”

“It still doesn't sound safe.” I said. “But if it’ll stop Chara, then okay.”

“welp, if it's okay with you then let's go.”

We got back to the lab, then Sans went back and got Sarah.

“How’s it coming, Alphys?” I asked her, after Sans had left.

“Uh, I’m almost done. Did Sans tell you about what we’re going to do?”

“Y-yeah.” I said nervously. “I-I'm a little scared, but if it’ll stop Chara, then I'm ready to do it.”

“That's the spirit! Don't worry, I'm sure it will be fine.”

“O-okay. When will we do it then?” I asked.

“When Sans comes back, then we can start hooking you up.”

“Okay then.” I said, still a little nervous. “What should I tell Sarah?”

“I-it depends. If the procedure is successful, then we don't have to do it on her too.” Alphys said nervously.

“Wait, what do you mean, do it on her too? I thought it was just me?”

“Well, if Chara can possess Sarah too, then we might have to do it to her also.”

“Would it be safe to do it on her?” I asked, worried for my sister.

“Y-yeah, for the most part.”

“What do you mean, for the most part? I don't want her to get hurt.”

“Oh, she won't get hurt, I enabled a system that will shut down the dt extractor if the procedure fails.”

“Okay then.” I said. Sans appeared next to me.

“okay kid, are you ready to start?”

“I guess.” I replied.

“D-don’t worry, I'm sure everything will go according to plan.” Alphys then muttered the words “I hope…” under her breath.

“What’d you say?” I asked her curiously.

“N-nothing.” Alphys sighed.

I looked at her. “Okay then. What do I need to do?”

“All you need to do is step inside the dt extractor. Inside, there should be a chair for you to sit in. When we get started, there will be a tube that will come out and connect with your soul.”

“Okay.” I looked to Sans. “And if something goes wrong…?”

“the machine will shut itself down.”

“Alright then.” I said, climbing inside. “Let’s start.”