Flashback: Chicago, a few days ago. Cora had finished speaking with a friend and had waved her off, when she caught site of a woman in the phone booth. She hadn't meant to eavesdrop, but then she heard Stefan's name. She walked slightly closer, using her hearing to listen in. "Let me guess…it ended in tears and heartbreak."

"Where are you?" She heard a voice on the other end of the line say. He sounded vaguely familiar.

"Why? Do you want to come rub sunscreen on my back?" The girl asked.

"I'm thinking Europe. Italy, maybe Or Spain. You were always a sucker for those lazy afternoons."

"Keep guessing, Damon. Bye-bye." The girl said. She hung up and walked out of the phone booth.

"Excuse me." Cora walked over to her. "I couldn't help but overhear. You know Stefan, as in Stefan Salvatore?"

"Sort of." The girl said. "I'm trying to help him, though he probably still sees me as the evil vamp who turned him." To Cora, that story sounded familiar.

"Katherine?" She asked.

"Not so loud. I have enemies in this town, if they find out I'm here…" The girl told her.

"I get it." Cora said.

"Well you obviously know me, but how do you know them?" Katherine asked. Cora looked at her.

"You told her that you were our sister?" Damon asked. Elena had been leaning against him, trying not to fall asleep. She seemed wide awake now, looking just as surprised as Damon.

"Did I really have another choice?" Cora pointed out. "I didn't want her thinking that there was anything between the three of us, and she obviously knew that I knew you two. Besides, on my part, at least it wasn't a total lie."

"You really care about them like siblings, don't you?" Elena asked.

"That's right. That's why it's not a complete lie." Cora said. "How do you know…"

"Because I feel the same way around my best friends and Matt." Elena told her. "And I have a brother."

"Hate to break up the girl bonding, but why were you in Chicago in the first place?"

"I went to support some of my friends. They had gotten a part in some musical at the theater." Cora explained. "Anyway, they had just left town while I decided to explore, and that's when I ran into Katherine. She explained everything to me."

"What did she say?"

"She said that Stefan was paying a debt to an Original vampire." Cora told them. "And that she wanted to help get him out of it. Of course, I was in, only it wasn't until tonight I learned how bad it was."

"But how'd you know where…" Damon asked.

"I followed Katherine to Mystic Falls." Cora said. "I watched from a distance and spent a couple days at a hotel. I just wish I could've intervened tonight."

"Hey, you couldn't have known things would turn out the way they did." Elena said. "I tried to help, but it wasn't enough."

"I'm sure you did your best, Elena." Cora said. "I want to help. I know it's dangerous, and that Originals can compel vampires, that's why I still have this charm." She held it up to them. "Though I can see why he put it in this case now. Even if I'm not directly touching it, it makes my skin breakout."

"Are you sure you want to get involved in this?" Damon asked, concerned. "It could be dangerous."

"You both helped me before, even tried to give me the chance to start over." Cora said. "I'd do anything to help my friends and family. I know it'll be hard, but if it means we get the real Stefan back, I'm in."

"We could use the extra help." Elena said. "After everything that's happened tonight, we could use more people on our side right now. And you seem to know a lot about this."

"I've always been good at observing." Cora told her. "And someone has to keep them from fighting, or worse, killing each other. Especially with Stefan's humanity off."

"I really hope you know what you're getting into here." Damon said to her.

"I know exactly what I'm getting into, besides, I know how to handle myself." Cora pointed out. "After all, I'm like you guys now and I know a lot about self-defense."

"It's good to have you on the team, then." Elena said, smiling slightly.

"There's a guest room upstairs if you need somewhere to stay." He told Cora as she left the room.

"Wow." Elena said. "She seems nice."

"She's a lot like you: compassionate, quick-thinking, and very smart." Damon told her. "You should probably get home soon." Elena nodded, though she still seemed only half-awake. Tomorrow, things would be different, though. She knew everything was about to change.