But the other part of me can’t help but see Quinn McCauley, my best friend, looking miserable. That part of me wants to help her.

It wants to help us.

Then there’s a third part that worries I’m a terrible sister because when I look at Quinn, my brain still thinks: best friend. It’s like those two words are written in big block letters above her head, and no matter how hard I try to erase them, they won’t go away. Of course I want Mabel back, but another awesome thing about this plan is that if it works, Quinn can be my best friend again.

It’s hard to admit, but I’ve missed her. I’ve missed her so much. Tears brim at my eyes as I think about just how much I’ve missed her.

I relax my fists. “You’re right. We have to just focus on fixing this. All of this.”

Quinn paces around the giant oak tree. Her feet crunch over dead leaves as she makes quick circles. “Can I say something without you getting mad?”

“Sure.” I don’t know if I mean it or not.

“I know—” She starts but stops. She keeps walking in circles.

“You know?” I prompt.

“I know that you want to think of this like a science experiment, and before you say anything, I know why. It makes total sense. That’s how it’s going to work. And that’s why I knew I needed your help because I knew I couldn’t figure out the science stuff.”

I mumble something, but she holds up her hand to shush me.

“I’m not done,” she says.

“Okay.”

“But I think you have to stop looking at this like it’s a puzzle where you’re collecting all the pieces. I know why you want as many details as you can get about Parker, but I think you have enough now. We’ve done the research part.” She scrunches up her face in thought. “That was one of the steps, right?”

I nod, and I’m about to recite all the steps to her and clarify that really the research step came before the hypothesis, but before I can get that out, she starts talking again.

“But it seems like now is the time to try. I mean, why not just try? I think we’re ready.”

“Wait. You mean try? Like right now? To just do it? To time-travel?”

She shrugs. “Yeah. I don’t think we need to do any more preparation. You’re the one who always told me that the most amazing scientific achievements seemed almost like magic at first. That’s what this is, right? A new scientific achievement.”

I clench my jaw. “It’s not magic. It’s science.”

“I know,” she says quickly. Her pace has picked up. Circle after circle. It makes me dizzy to watch her.

“But it’s going to feel like magic. And the thing I know about magic is that you have to look for it,” Quinn says.

All of a sudden, she stops moving. She looks right at me. “Do you get what I’m saying? There’s no equation to solve or puzzle piece to find. We’ve done that. Now there’s only us and this tree.”