Cora’s always taken things very literally. I mean, Mrs. Tanner would tell me that I was going to end up trapped in one of my daydreams if I didn’t learn how to stay in the real world. I never freaked out about that.

Cora narrows her eyes. “What? I have a lot of homework.”

“That makes sense. I mean, you’re in Honors Math and Honors English, right?” This is the first year we’ve had tracked classes. I’m not in Honors anything.

Cora nods. “So where are we going?”

“I want to show this—” I’m not sure if my brain is actually having a Freeze-Up or if these things—or rather this thing—is just really tricky to talk about. Whenever I’m thinking really hard about time travel, my brain feels like a piece of butter that’s going to slide right out of my skull and leak out onto the floor. Time travel is not an easy thing to understand and I don’t want to look stupid in front of Cora.

Cora blinks at me. I blink back twice. My heart turns into a balloon every time she uses that signal with me, inflating with all my memories of Cora, inflating with all my love for her. She doesn’t think I’m stupid, my brain says. She still cares about me. My heart inflates some more.

“I want to show you a place I think would be good to build our time machine,” I say.

“I don’t think we should build a time machine.”

“What? You read the—”

“A time machine isn’t practical.”

I maneuver around under a low, spiky branch and make sure Cora does the same. The last thing I need is her getting a gnarly scratch before I’ve even had a chance to show her the giant oak tree. “You used to be fascinated with time machines.”

“Yeah. When I was a kid.”

My balloon of a heart deflates a little bit. “But all the articles—”

“They didn’t say you had to have a time machine. Most of them mentioned wormholes.”

“A time machine is a way to find a wormhole.” I repeat that fact with confidence. I’ve read it over and over again. I’ve whispered it to myself before falling asleep and whispered it again when I woke up in the morning.

“But not the only way. And there’s no chance we could get the materials in time to build a machine. Wait. You weren’t really suggesting that we build a time machine, were you? We would need like a gajillion dollars.” Cora unfolds her fingers like she’s counting.

I hadn’t thought about that. I’d only imagined what the time machine would look like. A flashy dashboard with lots of fancy and futuristic knobs. A saucer shape with a metallic glow. Something beautiful, but also important-looking.

“I don’t know,” I say.

“Well, I don’t think it’s practical to build a time machine.”

“Um. Okay.” My brain is asking, Then what? But I don’t say it.

“I think we should try to find a wormhole without a time machine,” Cora answers my question without me having to ask.