Sure enough, the lights in the history classroom are still on. Through the small window in the door, I can make out his figure hunched over the teacher’s desk, stacks of papers laid out before him. It looks like he’ll be busy marking them for a while.

Perfect.

Now I just need to turn invisible.

“Sometime soon would be good,” Henry murmurs from close behind me, as if reading my mind.

I scowl but don’t reply right away, gesturing for him to follow me into one of the narrow adjoining corridors—far enough so that Mr. Murphy can’t hear us. The place smells like fresh printer ink and whiteboard markers. It smells like integrity, like academic success.

Another wave of nausea rolls over me.

“I’ve already told you,” I say as I resume my pacing. “I can’t control when exactly the invisible thing happens. It just does.”

Henry doesn’t move, though his eyes follow me as I walk, back and forth, back and forth. Someone once told me my stress was contagious, that it spilled right out of me. But maybe Henry is immune to it, untouchable, like he is with most things.

“In that case,” Henry says, “how can you be certain it’ll even happen tonight?”

“I mean, I’m not.” I sigh. “But it’s happened much more often in the evenings these past few weeks, and I can make a...a reasonable prediction based on the existing patterns. Like menstrual cycles.”

For a brief moment, Henry looks stunned. “I beg your pardon?”

“Menstrual cycles,” I repeat, very clearly, glad to see him squirm for once. “You know, like you can keep track of what time of the month it happens and know roughly when to expect it, but sometimes it still manages to catch you off guard. It’s like that.”

“Ah.” He nods, schooling his expression back into one of calm. “Right.”

And just like that, my momentary rush of satisfaction leaves, and the anxiety returns with double the intensity. I quicken my steps, wring my hands together. It’s a wonder Henry isn’t dizzy looking at me.

This is, without a doubt, the worst part of every mission: not the fear of getting caught, or even the guilt gnawing on my conscience, but the uncertainty. Never knowing when I’ll go invisible or when I’ll go back to normal.

Only a couple weeks ago, I’d spent an entire day standing around the school hall, waiting for my powers to kick in so I could finish what should’ve been a simple Beijing Ghost task. They never did. Henry had been surprisingly understanding about it, even though he’d chosen to wait with me too, but I can still taste the sharp, sour note of failure, still feel the heavy frustration of relying on something completely out of my control.

“Just relax,” Henry tells me, after I’ve paced the length of the corridor at least twenty times. If I were counting my steps, like Chanel does, I’m sure I’d have reached my daily goal by now. “Even if this task doesn’t go as we initially planned... What’s the worst that could happen?”