“You’re not that short,” I said, since I only had about four inches on her.

“I am, though,” she said, shaking her head, and I noticed, getting a little worried, that her hair didn’t move at all when she did this. “Oh my god, when I was in Copenhagen, it was the worst. Everyone there is tall. I was practically the shortest person around. You would totally have fit in. I love your T-shirt, by the way. Is it vintage?”

“Um,” I said, looking down at it, thinking that vintage was probably not the right word for it, but nodding anyway. “Kind of. It was my mom’s.”

“Awesome,” she said. “You can tell. Cotton only thins out like that with years of washing. I know a consignment shop in San Francisco that would pay you at least a hundred bucks for that.” She seemed to realize that we’d gotten away from the mission at hand, because she turned back to the window.

As I looked up at it, I couldn’t help but wish that Beckett had been with us, since he would have been able to get up there, no problem.

“Okay,” the girl said, looking from the window and back to me. “Maybe if you give me a boost?”

“Okay,” I echoed, trying to sound more sure of this than I felt. I met her eye, and we both started laughing, even though I couldn’t have said why.

“Oh my god,” the girl said, clearly trying to regroup. “Okay. Okay okay.”

I made a cradle with my hands, and she stepped into them. And while I tried my best to push her up, this quickly turned into the girl basically standing on my back while she grabbed for the windowsill.

“Are you okay?” she asked. “I’m so sorry. I can’t believe this. Am I hurting you?”

“It’s fine,” I managed as I tried to stand up and give her another boost.

“Got it!” she said triumphantly, but when I straightened up, I saw this was maybe a little optimistic, as she was hanging on to the sill, but seemed much closer to falling to the ground than getting herself into the window. “Um, sort of.”

“Here,” I said, grabbing one of her feet that was kicking in space as she tried to hoist herself over. “Maybe if I give you another push?”

“Yes!” she said. “Great idea. You’re a genius at this.” I held on to her foot, and she pushed off my hands and was able to swing one leg, then another, over the sill. She fell over the window with a thump that I could hear even from the ground. “Ow,” I heard her mutter from inside.

“You okay?” I called up.

A second later, her green head appeared in the window. “Fine!” she said. “Thank you so much! You saved my life. Or at least my hair.” She smiled at me, and then disappeared from view. I figured she’d gone to wash off the green mask, but found myself waiting by the window for just a few moments more, wondering if this was over. When she didn’t come back, I turned and walked down the driveway. As I got to the end and turned right on the road, in the direction that would take me back home, I realized that I didn’t even know the girl’s name.

When I started running in the same direction the next day, my muscles protested—loudly. But I didn’t even think about not going, though I hoped it wouldn’t make me seem like a stalker. It just felt like I’d seen the first five minutes of a movie, and I had to know what happened next. And if the girl wasn’t there, I wasn’t going to knock on the door or anything. I was just hoping that maybe she’d be outside again. When I got closer to her house, I felt my hopes deflate as I realized that the driveway and sidewalk were empty. It seemed totally obvious now that they would be. Did I just expect that she would be hanging outside, waiting around? I turned to head home, and as I did I noticed that there was writing on the ground, in chalk, the letters a mix of capitals and cursive.

Hey, running girl!! Thanks so much.

Hair is fine. J xo, SW

On the third day, I didn’t even try to run. My legs were killing me after trying to do two long runs when I was still out of shape. I’d gotten my mother to drop me off about a mile away, telling her that I wanted to scout a new run. I think normally she would have asked more questions, but Beckett had been throwing a temper tantrum in the backseat and her attention was divided. She told me to give her a call if I needed a ride home, reminding me not to be gone too long, since we had a family dinner planned.

If it had been one of the girls from school that I’d been trying to impress, I would have worn something different. One of my nicer dresses, the skirt my mother had just bought for me, the kind of clothes that always made me feel like I was pretending to be someone else altogether. But I found myself reaching for another one of my mom’s old T-shirts, the ones I only normally used for running or hanging around the house. I also put on some lipstick, even though I didn’t have anything close to bright red. As I looked in the mirror, I realized I still felt like myself, but a new version of myself, one I’d never tried out until today.

I walked slowly toward the girl’s house, trying to get my courage up. I had decided, back when I was getting ready, that I was going to go up and ring the bell. She’d left me a note, after all, and wasn’t that kind of like an invitation? But the closer I got, the more I began to question if I would actually be able to do this. Ring the bell of a mansion, and then when someone came to the door, ask for—who, exactly? The plan was seeming stupider and stupider the closer I got, but I made myself walk all the way up to the base of the driveway. The chalk message was gone, no doubt washed away in the thunderstorm that had woken me up at two a.m. I looked up the driveway for a moment longer, then lost whatever bit of courage had gotten me this far and turned to go.

“Hey!” I looked up and saw the girl leaning out of a second-story window. She smiled at me. “Hang on, okay?” I nodded, and her head disappeared inside.

I shifted from foot to foot, smoothing my shirt down, wondering why I felt so nervous. I was nervous around my friends at school, but that was more nervousness that I would say something stupid or find myself kicked out of the group. This was something else entirely.

“You came back!” I looked up and saw the girl was heading down the driveway, walking fast, then running for a few steps, then walking again. As she got closer, I saw she was holding a pair of sandals in one hand, swinging them by their long leather straps. She reached me and dropped them next to her on the ground. “I’m so glad you’re here! I wanted to thank you, but then realized I had no idea how to do that. Look!” She bent forward and shook her hair at me, and I realized that it was intact, and not the slightest bit green.