"I know this is hard, kiddo," Mom said one final time. "So that's why I thought you might like something to take your mind off of it." And then Mom reached behind her desk and pulled out a large white box wrapped in a beautiful blue ribbon.

Well, obviously I'd gotten presents from my mother before—good presents (signed first editions of A Spy's Guide to Underground Moscow don't grow on trees, you know), but I had a feeling this present was different. I felt like there was some kind of string attached.

"Go ahead," Mom said. "I think it should fit."

I untied the ribbon and let it fall to the floor, took the top off the box, and peeled away the layers of tissue paper.

"It's a dress," I said, stating the obvious—except it wasn't just a dress. It was red…and floor-length…and strapless! And I know normal mothers probably buy normal daughters strapless dresses all the time, for dances and proms and cello recitals and stuff, but the last time my mother had held a dress like that she'd been getting ready for a New Year's Eve party on board the yacht of a Middle Eastern arms dealer, so something about this dress felt…different.

"It's beautiful," I said.

Mom walked over to the microwave to pop in some frozen burritos. "I'm glad you like it. I thought it would look good on you."

Which, to tell you the truth, I sort of doubted, but I didn't think it was the right time to point that out.

"Uh, Mom…"

"I also thought it might come in handy in a week or so."

I sat there staring into the box, thinking that whatever was coming, it was big. It was important. And it required formal wear.

Chapter Fifteen

The Gallagher Academy has prepared me well for a lot of things, but none of those things are red. Or strapless.

Maybe my mother had forgotten that I was the girl nobody sees—The Chameleon—and chameleons simply don't walk around in formal gowns with empire waists and long gauzy skirts that flow when you twirl. It was as if my mother didn't know that this dress was for someone who was definitely supposed to be seen.

"What's the matter, Gallagher Girl?" Zach asked as we left COW the next morning and started the walk to C&A. "You seem…jumpy."

Well, he would have been jumpy too if he'd heard Bex's theory that a terrorist group was going to take over a prom and we were going to have to go undercover and stop it, but obviously I couldn't say that. And in a few minutes, after we'd settled into the Chippendale chairs of the Culture and Assimilation classroom, no one was saying anything.

"The all-school exam…" Madame Dabney exclaimed as she stood in the center of the room. Soft rays of early sunshine glowed around her, and her voice had taken on such a dreamy quality that I almost expected harps to start playing as she floated across the floor. "Ooh, ladies," she said, then rushed to add, "…and gentlemen. In all my years of teaching at this fine institution, I have never had the opportunity to organize such an exciting educational experience."

Liz went still, and Eva and Tina tore their eyes from Grant's muscular forearms.

"This Friday evening, all students in grades eight through twelve will be invited to a formal examination." Madame Dabney waited for what she must have expected to be a standing ovation. "A ball, ladies and gentlemen," she explained when no one broke into applause. "There's going to be a ball!"

Tina gasped, and Liz's eyes went wide in a way that can only be induced by the combination of both tests and high heels; Jonas swallowed hard and turned the exact same shade of red as the dress that was hanging in my closet—the dress I was going to have to wear … for a grade!

There had to be some kind of mistake, I thought. Surely Bex was supposed to get that dress and I was supposed to get instructions on how to access the dusty, dirty, mice-infested ductwork of the Russian Embassy or something.

Mice I can handle. Strapless bras? Well let's just say, I'm the kind of girl who likes things sufficiently strapped.

"Tomorrow during this time, you will each be fitted for a gown." She beamed at the girls. "And tuxedos," she said as she turned to the boys. "On Friday evening you will be asked to participate in a cumulative examination—a night that will encompass everything we teach. And you will be expected to dance."

At that point I'm pretty sure every other girl in the room heard "dance."

But I thought back to Bex's words as we'd stood in the deserted East Wing, and I, personally, heard "rematch."

There's something to be said for having Joe Solomon blindfold you and fly you to D.C. After all, the hard part about top-secret, clandestine missions isn't the shock or the fear or the helicopter turbulence. The hard part … is the waiting. And I know I wasn't the only Gallagher Girl to feel that way, because in the week following the ball announcement, there were so many rumors floating up and down our halls, even I could hardly keep them all straight.

For example:

Instead of having a comprehensive exam, like we'd been told, we were actually going to have to infiltrate a prom that was going to be taken over by terrorists. FALSE.

All the girls in the eighth grade class now hated Macey McHenry since all the boys in the eighth grade class were in love with her. TRUE.

Chef Louis was going to serve poisoned appetizers so that we would have to concoct antidotes. Or die. FALSE.

Thursday's P&E lesson centered on defensive positions that could give the term "kick pleat" an entirely new meaning. TRUE.

Body-waxing as a torture-slash-interrogation tactic is illegal under international law. FALSE. (But if the yells coming from Tina Walters's bathroom were any indication, it totally should be true.)

By Friday morning you couldn't walk down the hall without hearing at least a dozen conversations that involved bobby pins (and not in the usual lock-picking and/or self-defense contexts). A part of me was a little concerned by the state of my sisterhood, but another part of me knew that half of a mission's success is determined before the mission even starts. Prep work matters. And, it turns out, that goes double for missions that involve formal wear.

"Will you hold still?" Macey demanded as she grabbed my jaw and held my head steady (because everyone knows eyeliner can be lethal in the wrong hands). But how could I possibly sit there as if my liquid liner were the most important thing in the world? We had less than an hour before the ball began, and that was time I could have been using to go over my chemistry textbook or my CoveOps notes. Didn't my best friends know that this was an all-school exam—that's every subject, and this was my big chance at redemption?

But no. I couldn't study at all, because Liz was doing really painful twisty things with my hair while Macey gave me a three-minute lecture on the state of my pores. Meanwhile, Bex was busy sewing one of Dr. Fibs's bulletproof cups into her Wonderbra instead of the foam things it came with. And I couldn't help but think that spy stuff is hard. Girl stuff is hard. But I doubt there's anything harder than spy-girl stuff.

I didn't even want to think about what the boys were doing then, because…hello … I'd seen the tuxedos hanging in the C&A classroom, and they were all black. And so were their shoes. And their ties. And every single boy from the Blackthorne Institute had hair not much longer than a buzz cut, so I seriously doubt they were going through this. Nothing in life…much less espionage … is fair.

It was nearly seven o'clock. Our suite smelled like perfume and curling irons that had been on too long. And down the hall, I heard Anna Fetterman yell, "Does this make me look fat?" even though she weighs one hundred and two pounds. It wasn't just another night at the Gallagher Academy. This wasn't just another exam. And I, for one, wasn't ready. In a lot of ways.

"Can somebody zip me?" Eva cried, running into the room as quickly as is possible for a five-foot-two-inch girl in three-inch heels. Tina appeared in our suite and asked if we had any duct tape (and I highly suspect she needed it for a very nontraditional use).

Everything seemed brighter and louder, and I couldn't shake the feeling that we were getting ready to be tested in a lot of ways, so I pulled on the red dress. I knew it was time for me to stop hiding—even in my own room. I blocked out the fact that it was Friday night. And that two miles away, a different kind of school was getting ready for a very different kind of dance.

I started for the door and said, "It's time."

I never really knew how uniform our uniforms made us look until I stood at the top of the Grand Stairs, looking down into the foyer. Girls of every size, shape, and color wore shimmering saris and elegant gowns. For the first time I saw what I had always known—that there's not a corner of the world we can't disappear inside.

"You look lovely, ladies." Madame Dabney stopped in front of us and turned to Professor Buckingham. "Oh, Patricia, don't they look lovely? I wish I'd brought my camera…Maybe I should go back…Wait." She stopped suddenly as if she'd just remembered something. "There's one in this brooch." And then she herded Bex and Macey together while she took a picture with the pin that held a gauzy silk scarf around her neck.

Everyone smiled. And I suppose we did look lovely. Bex's dress was long and black with a strappy back that totally showed off her muscles; Liz looked like the tooth fairy (but in a good way), in a soft pink gown with a full skirt. And Macey, of course, looked like a supermodel in her simple green gown and her hair in a pony tail (I know—a ponytail? Unbelievable.)

The front doors opened, and I saw some guys from the maintenance department coming in, probably to help even out the male-to-female ratio a little bit. (Let me tell you, the Gallagher Academy maintenance department uniforms aren't nearly as flattering as tuxedos.)

Three of the eighth grade boys pounced on Macey, begging her to save them dances, and then I heard a voice, low and strong behind me.

"Well," Zach said slowly, taking in everything—from the shoes I couldn't walk in, to the hairdo Bex and Macey had insisted on. Then he leaned back against the railing and crossed his arms. "You don't look hideous."

I was pretty sure that was supposed to be a compliment, but my understanding of boy dialect was still a little rusty, and Macey was nowhere to be found, so I had to wing it. "Ditto."

Oh my gosh, I thought. Is he smiling? Is he laughing? Is it possible that Zach Goode and I just had a formally attired, preclandestine-mission moment?

And maybe we had, but I'll never know, because just then my heel caught on my hem, and it took every ounce of grace I could muster to avoid falling on my face and out of my dress (you know…the strapless one).

"Easy, Gallagher Girl," Zach said, taking my elbow in the way Madame Dabney had taught the boys the day before.

I pulled my arm away. "I am perfectly capable of walking down the stairs by myself." He'd obviously forgotten that I was also capable of throwing him down those stairs, but then Madame Dabney floated by. "A lady always gracefully accepts a gentleman's arm when offered, Cammie dear."

So see—I totally didn't have a choice—not with Madame Dabney standing there taking pictures of us with her jewelry.

I accepted Zach's arm, and we walked down the stairs, toward the biggest (and…well…fanciest) test ever. But was Zach nervous? No. He was just smiling that same I-know-something-you-don't-know smile he'd first given me in the elevator in D.C.