I thought I was going to be sick—seriously—right there in front of eight security cameras, my favorite teacher, and…Zach.

I'd thought he was chivalrous (but he wasn't). I'd thought he was cute (but tall, dark, and handsome is highly overrated when you think about it). And worst of all, I'd thought he'd been flirting…with me.

A group of tourists wandered into the shoe exhibit and pressed closer to the case. I was jostled by the crowd, then blinded by a flashing camera. Mr. Solomon put his arm around my shoulders and guided me to the doors.

I looked back toward the slippers.

But Zach was already gone.

How weird was the helicopter ride home? Let me count the ways:

In an effort to make themselves less tailable, Mick and Eva had traded their school uniforms for jumpsuits from the National Park Service maintenance staff.

Kim Lee had fallen down the stairs at the National Gallery, so she had to sit with her ice-packed ankle propped on Tina's lap.

Courtney Bauer was still wet, following a very unfortunate Lincoln Memorial Reflecting Pool incident.

And Anna Fetterman kept staring into the dark with her mouth open because, of all the Gallagher Girls on the Mall that day, she was the only one to achieve our mission objective (yeah, you read that right, Anna Fetterman!), and she was the most shocked person of all.

Even Bex had picked up a tail on her way out of the Metro station and didn't make it to the museum on time.

So that's why the entire sophomore CoveOps class from the Gallagher Academy for Exceptional Young Women sat in silence, watching the Washington Monument fade into the dark night while the helicopter rose, carrying us home.

I thought there would be questions. And theories. But even Tina Walters—the girl who had once hacked into a National Security Agency satellite in order to look for the alleged boys' school—didn't have a thing to say.

After all, it's one thing to learn there's a top-secret school for boy spies.

It's another to find out they might be better than you.

The countryside shimmered beneath us, and the mansion finally came into view, lights shining through the windows and reflecting off the snow.

I felt the helicopter touch down, saw the snow swirl around us as Mr. Solomon reached for the helicopter door, then paused.

"Today I asked you to do something that maybe fifty people in the entire world can do," he said, and I thought, This is it—a pep talk, a debrief. Or at least an explanation of who those boys were and why we were meeting them now. But instead, Mr. Solomon said, "By the end of this semester, there had better be fifty-eight."

"You really saw some?" Liz said an hour later. Sure, we had the stereo blaring and the shower running, but Liz still whispered, "They really…exist?"

"Liz," I whispered back. "They're not unicorns."

No," Bex said flatly, "they're boys. And they're…good."

Dampness weighed my hair, steam fogged the bathroom mirror, but the four of us kept the door closed, because A) Steam is excellent for your pores. And B) The biggest news in the history of our sisterhood was sweeping through the halls of a place where eavesdropping is both an art and a science. So needless to say, my roommates and I weren't taking any chances.

"Maybe it's not what you think," Liz said. "Maybe they weren't from Blackthorne at all. Maybe they just looked young. Maybe—"

"Oh," Bex said simply, "it was them."

As I dropped to the edge of the bathtub and rested my head in my hands, I knew nothing hurt as much my pride.

"I can't believe I actually talked to him," I finally admitted. "I can't believe I actually told him where I was going!"

"It couldn't have been that bad, Cam," Liz said, dropping to sit beside me.

"Oh, it was worse! He was…and I was…and then…" But I gave up because, in all of my fourteen languages, there wasn't a single word that could express the anger-slash-humiliation that was coursing through my veins.

"So," Macey said, hopping onto the counter and crossing her long legs, "just how hot was this guy?"

Oh. My. Gosh.

"Macey!" I moaned. "Does it matter?"

Bex nodded. "He was pretty hot."

"Guys," I pleaded, "the hotness is really beside the point."

"But exactly what kind of hot was he?" Liz asked as she pulled open her notebook and grabbed a pen. "I mean, would you say he was pretty-boy hot, like Leonardo DiCaprio the early years, or ruggedly-handsome hot, like George Clooney the later years?"

I was about to remind her that neither kind of hot could justify my revealing the location of a clandestine rendezvous, when Bex answered for me. "Rugged. Definitely rugged." Macey nodded her approval.

Down the hall, the rest of the sophomore class was hacking into the Smithsonian surveillance system and running the pictures of every male between the ages of twelve and twenty-two who had been on the Mall that day through the FBI's facial recognition program. At least a dozen girls were in the library scouring the very books we had abandoned days before.

Still, no one had said the name Blackthorne. No one had mentioned the East Wing.

Liz closed her notebook. "Well, now we know what your mom and Mr. Solomon were talking about. And it's over." She smiled. "You never have to see him again."

Then she seemed to consider the naiveté of what she'd just said. "Do you?"

By four a.m. I was seriously starting to resent Joe Solomon and all of his "use your memory" training, because at that point I would have given my entire life savings (which were $947.52) to forget what had happened.

Bex was lying in the light of the window, smiling a devilish smile, probably dreaming of hostile takedowns and elaborate covers. Liz was curled up against the wall, taking up no more room than a doll, and Macey lay on her back sleeping peacefully despite the wheezing sound of air rushing past the great big diamond in her nose. But me? All I could do was stare at the ceiling and pray for sleep, until I finally threw off my covers and brought my bare feet to the cold hardwood floor.

I swear I didn't know where I was going. Seriously. I didn't. I just slipped on a pair of tennis shoes—no socks— and crept toward the door.

Every spy knows that sometimes you just have to go on adrenaline and instinct, so when I found myself wandering the dark empty hallways, I didn't ask why. When I started down the second-floor corridor, I didn't tell myself to turn around.

Moonlight fell through the stained glass windows at the far end of the corridor. I crept toward the tall bookcase at the mouth of the Hall of History and the hidden passageway it conceals. Then I heard the floor creak behind me and saw the beam of a flashlight burn through the hall before shining in my face. I threw my hands over my eyes and started preparing alibis. (I was sleepwalking. … I needed a glass of water. … I'd dreamed that I hadn't turned in my COW homework for Mr. Smith and was going to check…)

"You didn't think we'd let you go without us, did you?" Bex asked.

When Macey finally lowered the flashlight, I could see Liz shivering in her thin nightgown and Bex holding open a small black case; her trusty silver lock picks shimmered in the light.

No one had to say where we were going. We'd started down the path days before and were finally going to see where it ended. While Bex worked on the lock to the East Wing, I didn't look into the Hall of History; I didn't look at my mother's dark office; and most of all, I didn't think about all the promises I was no longer in the mood to keep.

"Got it," Bex said in record time, and then the door swung open.

We stepped into a hallway we used to know. Now it led to a large open room. Deserted classrooms ringed the space, but the desks were gone. A door stood open, and I could see that a bathroom had been modified to stand between two…bedrooms? The scent of sawdust and fresh paint filled the air.

"They look like…" Liz started but trailed off. "Suites?" she said, her genius mind trying to wrap itself around such a simple fact.

There were beds and desks and closets. The rogue-florists theory didn't seem scary anymore. "You know what this means?" Bex asked.

There was only one thing it could mean.

"Boys," I said. "Boys are coming to the Gallagher Academy."

"Yeah." Bex smiled. "And we're going to get a rematch."

Chapter Eleven

The Gallagher Academy is a school for exceptional young women for a reason. Actually, lots of reasons.

For example, by having only girls' bathrooms (not counting the faculty lounges), the mansion is able to devote valuable square footage to things like chemistry labs and TV rooms.

Also, the average teenage girl in a coeducational environment is likely to spend one hundred hours a year getting ready for school, when that time could be used for sleeping or studying or debating the merits of foot vs. vehicular surveillance in an urban setting.

But the biggest reason the Gallagher Academy is a school for girls is that in the late 1800s it was perfectly acceptable for boys to learn math and science and how to hold their own in a duel, while girls like Gillian Gallagher were forced to master the fine art of needlepoint.

Gilly couldn't join the Secret Service—even after she'd saved the life of a president—because the other agents were afraid her hoopskirt might get in the way (when, in truth, hoopskirts were excellent for smuggling sensitive information and/or weapons).

So Gilly did the next best thing: she opened a school where proper young ladies could learn all the things they were never supposed to need, a place where young women were free to become exceptional without the pressure or influence of boys.

But now … more than a century later … all of that was going to change.

At breakfast the next morning, my roommates and I stared at our plates, not really listening as Anna Fetterman recounted the day before in detail.

"Und dann sah ich ihn in den Wandschrank gehn and ich wusste, dass ich ihn dort einschliessen musste um dann die Stufen hin unter gehen zu koennen," she said, and I have to admit, locking the agent on her tail inside a closet at the top of the Washington Monument was pretty ingenious of her, but I was in no mood to take notes.

"Cammie. When do you think they'll…you know…" Liz whispered, despite the sign telling us we were supposed to be speaking in German. "… come?"

I didn't have a clue. In the last twenty-four hours, the entire world as I knew it had changed, so I wasn't in a hurry to give the boys' arrival a time frame—to make it in any way real.

But then the reality of the situation stopped being an optional thing.

My mom rose from the staff dining table and took the podium. "Excuse me, ladies, but I have an announcement to make."

The doors at the back of the room swung open.

I knew that nothing at the Gallagher Academy for Exceptional Young Women would ever be the same again.

Forks dropped. Heads turned. For the first time in twelve hours, there wasn't a single whisper inside our stone walls.

Gallagher Girls are supposed to be prepared for anything and everything. Even though I'm pretty sure we could handle an invasion by enemy forces, one glance at my classmates told me that not a single Gallagher Girl felt fully prepared for the sight of fifteen boys standing in the doorway of the Grand Hall.