French must be the one chink in Heather’s perfect armor, because she’s in the same class.

  Before Izzy and I headed separate ways at the end of the hall, Izzy shook my hand, like a general sending his most trusted soldier off to war. “Good luck,” she said solemnly. “Or should I say, bonne chance?”

  “Same to you. See if you can catch up with Tom, check that he’s OK.”

  “Will do,” Izzy agreed, and she went into her classroom.

  I’d decided my strategy was going to be to start a conversation with Heather and see how she acted with me. I figured I should be able to sense whether there was something different about her.

  The problem was, I hadn’t quite decided how to actually start the conversation. You can’t exactly walk up to someone with whom you’ve only ever traded dirty looks — apart from in French, when you are forced to talk to each other — and say, “Hi there, I know we’ve never really spoken, other than to say ‘Bonjour, je m’ appelle Jessica. Comment vous appelez-vous?’ in a very bad French accent, but I’ve recently found out that I’ve got a magical superpower and, hey, guess what! I think you might, too — even if you don’t know it yet — so I thought maybe we should try being friends!”

  And I was pretty sure that wouldn’t be classified as secretly staking her out, either. I’d have to figure it out as I went along.

  I walked through the door just before Ms. Hadley got there. I glanced around the room and there was just one seat left — next to Heather! Normally the worst seat I could have landed myself with; today it was ideal.

  I slid in next to her and gave her a big smile. She glared at me, then looked away.

  This wasn’t going to be easy.

  A moment later, Ms. Hadley closed the door behind her and looked around the class. Her eyes zoned in on me. “Jessica, were you late?” she asked.

  “Um. I don’t think so. I was here before you,” I said, with a cheeky smile, hoping she’d find me funny and cute.

  “Détention,” she said. In French.

  I sighed as Ms. Hadley told us to get our books out. Then I nearly fell off my chair as Heather nudged me.

  “Whoa. That was harsh,” she whispered.

  “Thanks,” I said with a grimace. OK, so it wasn’t exactly “Hey, now that we’ve exchanged five words, let’s be BFFs,” but it was a start.

  I spent the rest of the class with two aims. Aim one: avoid getting into any more trouble with the teacher. I achieved this, as she called me over at the end of class and said she’d decided to let me off the detention since I’d contributed so well, and could I please try to keep that up in the future.

  Aim two: smile at Heather as many times as possible so that by the end of a forty-minute class she’d forget our year and a half of animosity and not walk off if I tried to start a conversation with her.

  It was during one of these smile attempts that I noticed her hand. She was wearing that sparkly ring again. I was sure I’d never seen her wearing it before last Thursday. Admittedly, I didn’t look too closely at her as a rule, but it was bright yellow and shiny and definitely looked new. Might she have gotten it as a birthday present? Was it possible that my suspicion was right — that Heather had already discovered that she had a superpower?

  At one point, she caught me staring and I glanced away, but not before noticing that her cheeks had flushed a little and that she quickly put her hand in her pocket.

  A bolt of excitement surged through me. I was right! I was sure of it. Well, not sure — it was just a feeling, but a strong one. By the end of class, I was too impatient to spend the next few days secretly staking her out. If Heather was like me, I had to know. Now.

  She was in front of me as we filed out of the classroom. Once we were in the hall, I seized the moment before my brain seized my courage.

  “Hey,” I said in my best now-that-we’ve-bonded-in-French-class-I’m-sure-you-regard-me-as-one-of-your-best-friends voice.

  Heather turned around.

  “Nice ring,” I said, pointing at her finger.

  Her face clouded over for a second. The way it might have if I’d said, “Hey, you’re looking a bit drab today. You almost look as plain as the rest of us.”

  She recovered quickly, though, and gave me a tiny smile. “Thanks, it’s citrine,” she said, holding out her hand and looking at the ring. “It was a birthday present.”

  “Me too!” I burst out. “I mean, I got something for my birthday, too!”

  Duh! Most people do get presents on their birthday! Heather was giving me an OK-I’m-going-to-walk-slowly-away-from-the-crazy-person-now kind of look. I had to rescue this.

  I reached under my shirt. “I mean, I got jewelry. A necklace. On my birthday. Same day as yours.” Smooth, Jess, smooth.

  I watched Heather’s face for a reaction. I didn’t see one. Had I been wrong after all?

  “Oh. Right,” Heather said. “The thirtieth of March?”

  “Yep. Same day. Imagine that, huh?”

  “I don’t . . . I mean, I didn’t realize it was your birthday, too.”

  Obviously not, as you’re always too wrapped up in your own celebrations to notice anyone else around you, I would normally have replied. Instead, I smiled and said, “Don’t worry about it. Anyway, belated happy birthday — and thanks for being nice to me in French.”

  Heather gave me the kind of look you might give to a stalker you didn’t want to encourage but didn’t want to offend, either, because you’re a nice person. Was she actually a nice person and I’d never realized? “You’re welcome,” she said with what looked suspiciously like a shy smile.

  Heather, shy? Nah, it was much more likely to be a sneer. She’d probably tell her friends all about the stupid conversation with the pathetic loser — aka me — as soon as she saw them.

  But there was something about the way she smiled that spurred me on. Before I could stop myself, I gathered all my nerve and a bunch of words charged out of my mouth without checking with my brain first.

  “Look. Um. If you’re not busy tomorrow at lunchtime, do you want to do something with me?”

  “Do something with you?” Heather asked in a voice that was so full of shock I wondered for a second if I had actually asked her if she’d like to rappel off the Eiffel Tower on the back of an elephant.

  “I . . . yeah, OK, sorry.” How on earth could I have thought Heather would want to spend time with me?

  “I have volleyball Tuesdays at lunch,” she said.

  In other words, Leave me alone, loser.

  “Yeah. Of course,” I said. And then, I don’t know what made me do it — probably the thought that this might be my only chance — but I found myself still talking. “Look,” I went on. “If anything kind of . . . happens, or if anything has already happened, maybe something weird, that makes you wonder if we’ve got more in common than you thought . . . and you want to, kind of, you know, hang out, how about Wednesday, then? No pressure. I’ll be in the art room at lunchtime. Maybe see you there.”

  For a moment, Heather almost looked scared — as if I’d just told her she’d been walking around with her skirt tucked into her underwear all day. Then she kind of shook her head and gave me her professional class-president smile. “OK, maybe,” she said, “if I’m not busy. But thanks either way,” she added, with one final thank-you-please-leave-me-alone-now-you-weirdo look.

  “Anyway, got to go,” I said, and before I could dig myself into a bigger hole, I turned and left her there. The last thing I needed was to be late for my next class and get into trouble yet again.

  I filled Izzy in at lunchtime. We agreed that, since I’d as good as followed Heather around with a sign saying, I’M A WEIRDO. PLEASE BE MY FRIEND, and since we’d disturbed Tom so much that he’d avoided us all morning, we’d probably done everything we could, for the time being.

  “I’ll talk to Tom in physics,” Izzy suggested. “See if he’s gotten over it yet.”

  “Why don’t you tell him about Heather? See if he
’ll join us on Wednesday, too?”

  “Good idea. Plus, that gives him another couple of days to get his head around it all.”

  “Sounds like a plan,” I agreed.

  It also gave us two days to figure out what in the world we were going to say, on the off chance that either of them actually turned up.

  And, in the meantime, there was this evening to worry about — the real stakeout.

  On Monday evening, I discovered something that I imagine is one of the biggest secrets in the world of undercover policing. A stakeout is not actually all that much fun. It is certainly neither cool nor glamorous, and is possibly the most boring way you could spend a couple of hours.

  My back was aching from crouching behind a hedge, my neck was hurting from craning to look down the road, and I was getting cold. Plus, it was a little creepy. It was starting to get dark, and coming up with a plan that involved two girls hiding behind a bush on a quiet street at night suddenly didn’t feel like our cleverest moment ever.

  Then Izzy grabbed me.

  “Jess!” she hissed. She was pointing through a gap in the hedge toward the lab. “Look!”

  I peered through the hedge and saw what she was pointing at. Someone was going into the lab! Nancy was right — they did have a burglar!

  Izzy shoved me. “You need to go. Quickly!”

  Suddenly the little-creepy thing became a totally-flipping-crazy-and-terrifying thing instead.

  “Wait — what if this person’s legitimate? What if it’s the doctor?” I pointed out.

  “Oh. I hadn’t thought of that.” Izzy thought for a moment. “Look, if it is someone who’s supposed to be there, then it won’t do any harm to check, and if it isn’t, then we’ll have caught the burglar. Win-win!”

  “But what if they see me?”

  “They won’t! You’ll be invisible! Go on, quick. They’re fiddling with the keypad already. You can follow them in.”

  There was no time to spare, so rather than hang around panicking and fretting and putting it off — which was what I suddenly realized I mostly wanted to do — I closed my eyes, emptied my mind so I could turn invisible, and stood up.

  “Wish me luck,” I whispered.

  Izzy reached out to touch my arm. She missed it — as I was already invisible and had started moving away. “Good luck. You’ll be fine. I’ll be right here,” she told me.

  “OK. You be careful, too,” I said. And then I hurried away from the hedge, crossed the road, and crept up behind the person heading into the lab.

  I sneaked through the front door and followed through the sci-fi door into the lab. It was only when the figure turned and pulled down his hood that I saw his face for the first time.

  I nearly gasped out loud. I knew him!

  It was a boy from my school. From my year! He was in the other class, so I didn’t know him well. In fact, I’d never spoken to him, but I’d seen him around — Max Something-or-Other.

  What on earth was he doing here?

  I know that, scientifically speaking, it almost certainly isn’t possible, but I could swear I didn’t breathe for the next thirty minutes. Didn’t breathe, didn’t think, didn’t move. Didn’t do anything except watch Max wandering around in the lab.

  I didn’t know much about him. To be honest, the only reason I’d noticed him at all was that he was kind of a big-mouth. One of those boys who seem to think it’s a weakness to smile or be nice to anyone and who always make sure their stupidest comments are said loud enough for everyone to hear.

  Not a bully, exactly, just not pleasant, and I’d heard him get into arguments with a few of the other boys after school. I couldn’t tell you what they argued about. I’d never hung around long enough to find out, but I’d seen enough to know that this boy wasn’t someone I wanted as my best friend. And if he was as unpleasant as he seemed, the thought of him finding out about my secret was not on my list of top things I would love to happen next.

  Which was why I held my breath for approximately half an hour, crouched down below a stool — even though I was invisible — and prayed he would leave soon.

  Unfortunately, he didn’t. He kept wandering around the lab as if he had all the time in the world. He didn’t seem to be looking for anything in particular. Every now and then, he’d lean over a table, study something on it, put the occasional thing in his pocket, and move on.

  From my hiding place, I couldn’t see exactly what he was picking up. I was fairly sure he’d taken a few crystals, as they were all over the place. But what did a boy like him want with rubies and moonstones?

  At one point he went to the far wall and opened a cupboard. There were loads of tiny bottles on a shelf inside. They looked like those perfume samples Mom sometimes gets in magazines. Max reached into his pocket and pulled out an identical bottle. He looked at it for a second, his hand hovering in front of the cupboard as if he were about to put it in, then changed his mind and put the bottle back in his pocket.

  Eventually, Max seemed to have had enough and headed out into the hall. I silently crept across the lab behind him.

  He opened the front door, then left it open as he did his coat up. Time to make a run for it. I shuffled toward him. Was there enough space to get past without touching him? I pondered for a moment, then decided I didn’t have any option. I squeezed through the space between Max and the door. Two seconds later, I was out of there!

  I was halfway down the path when I heard him.

  “Hey, is someone there?” he called.

  I froze on the spot. I looked down at myself. Invisible. Totally. He couldn’t see me.

  I didn’t wait any longer. As silently as I could, I crept to the bushes, hissed at Izzy to follow, and ran all the way to the bus stop.

  The next day at school, I could hardly believe who I bumped into on the way into assembly. And I mean actually, literally, bumped into — I bashed my face on the back of his shoulder while I was walking along talking to Izzy and not looking where I was going.

  Max turned to scowl at me. I stopped breathing, gaped openmouthed at him, and waited for him to recognize me.

  “What are you staring at?” he asked in his normal rude way.

  Phew! He didn’t recognize me. Well, of course he didn’t recognize me. He hadn’t seen me. I’d been invisible!

  I’d told Izzy everything when we’d gotten back to her house the night before, and she could see that I’d been thrown by bumping into him.

  “She doesn’t know,” Izzy said. “It hasn’t got a label on it.” And with that, she grabbed my arm and pulled me in the opposite direction.

  I risked a glance in Max’s direction before Izzy pulled me away. He had a strange expression on his face. Our eyes met, and for a millisecond, I thought I saw something different in them. Something I’d never seen before. A kind of recognition. What was he seeing? What did I recognize?

  Izzy whispered to me as we walked down the corridor, “I still don’t see what he would want with a bunch of crystals.”

  “I know,” I said. “It doesn’t make any sense, does it?” Just like it didn’t make any sense that I’d felt a strange kind of connection when our eyes had met. I didn’t tell Izzy that, though. She’d only tease me.

  “I mean, could he be involved with the lab, somehow?” she went on.

  “I doubt it. I think he’s too young to be a lab technician, don’t you?”

  We fell quiet while we both thought.

  “So what are you going to do?” Izzy asked eventually.

  “I don’t know.”

  “You want to tell Nancy? I mean, he probably is the intruder she was worried about.”

  “Yeah. He probably is,” I agreed. “But I don’t want to tell her. Not yet.” I wasn’t sure why. It was probably either the fact that we’d have to explain our unauthorized stakeout or not wanting to turn Max in before I knew exactly what he was up to — or perhaps a combination of the two. There was something stopping me; that was all I knew. “I’ve got an idea, though.”
br />
  “Spill,” Izzy said.

  “How about I just find out from him?”

  “From Max? What, like, ask him?”

  I laughed. “Er, no. I can’t see him happily sitting down and opening up about breaking into a strange lab in the middle of the night to some girl he’s barely spoken to, can you?”

  “What, then?”

  “I follow him home after school. See what I can find out. If he really is the culprit, what does he want the crystals for? What’s he doing with them?”

  Izzy’s eyes crinkled at the corners as she understood what I was saying. “And he won’t even know you’re there . . .”

  “Because I’ll be invisible!”

  “Brilliant plan!”

  And, yeah, OK, it was perhaps a brilliant plan. It felt bonkers and possibly risky, too, though. He wasn’t exactly the kind of boy you wanted to annoy.

  But it was the best option. I didn’t want to tell Nancy about him until I knew what he was up to. She was expecting a full-on burglar, but Max was just a kid my own age. For whatever reason, I felt that I owed it to him to find out more before potentially landing him in a whole heap of trouble. I also wanted to figure out more about the way he’d looked at me. There’d been something in his eyes — as if we had something in common — and I needed to find out exactly what that was.

  “All right, that’s that, then,” I said. “I’ll follow him home today.”

  I sat on the bus, five rows behind Max, and studied the back of his head. A messy, curly brown mop. It didn’t really give much away. I looked out the window instead.

  Just before the fourth stop, Max rang the bell and stood up. I followed him off the bus and walked along the streets behind him, keeping a respectful distance.

  I felt like someone in a spy movie, trailing their mark without being spotted. Although, to be fair, it was a lot easier for me to do the not-being-spotted thing, given that I kept myself invisible for the entire time.