The Crypt wasn’t a friendly room. It might be convenient, smack in the middle of the Capitol building with doorways leading everywhere. But it wasn’t a place that invited you to stick around and make yourself comfortable. Stone floors and stone columns made it a cold place. During the day, it was crowded with school groups, kids wearing matching neon green tee shirts. Those kids ignored the tour guides and made fun of the exhibits. They never looked at the ancient wooden clock from the old House chamber. They walked right past the replica of the Magna Carta inside its giant plastic box.

The one thing they did like was the miniature model of the National Mall. It was one of the few things in the Capitol that you could touch without getting yelled at. Tiny white plastic versions of the Lincoln Memorial and the U.S. Capitol sat at opposite ends on top of a long table. In between, there were miniature memorials and monuments and museums on the Mall. It was my favorite thing in the Capitol, too.

That was why I had come to the Crypt this afternoon. I wanted to memorize every building on the National Mall so that I would know as much about Washington as Papa. The table was just my height. I could look from one end of the Mall to the other without standing on tiptoe. Of course, there was another reason I was in the Capitol Crypt: I had no place else to go. My sister Gabby had band practice, marching around her high school football field with a clarinet. My grandmother was coming east to take care of us, but not for another two weeks. Until then, I had to come straight to the Capitol after school and wait until Papa finished working. Papa said I could go over to a friend’s house to do homework. But after a month at my new school, I still didn’t have a single new friend.

So I came to the Crypt, to study the model of the National Mall. There was something weird about it. There were two Washington Monuments right in the middle. I don’t know why. I wanted to ask Papa about it. But first, I had to find my sweatshirt. I started my search by circling the room, ignoring those Founding Fathers watching my every move. The Crypt was dark and echoey in the late afternoon. Strange shadows painted the arched ceiling. The ancient air conditioner wheezed as if it was about to die at any moment. The Crypt never felt scary in the middle of the day when tour guides in red jackets used their outside voices, warning kids not to lean on the display cases. Now all those bored eighth graders were back on buses, going home to Pennsylvania or Delaware or New Jersey.

All the tour guides had traded in their official red jackets for overcoats and scarves and were heading to the Metro. It was just me here in the Crypt.

Me...and something else.

I felt a tingling behind my ears, a sense that I wasn’t alone. I looked behind me. Nothing was there. “Hello?” I said, trying not to squeak. There was no answer.

The saucer-shaped ceiling lights were turned down low. Anything could be hiding behind the fat columns. Anything. My navy fleece wasn’t here, but something else was.

I tried again. “Hello?”

Don’t be a baby, Fina, I told myself. You’re ten years old now. Or “double digits” as my sister Gabby called it. You’re too old to be afraid of the dark. Don’t be a scaredy-cat. I tried to stand a little bit taller, but that was hard to do when you’re shorter than everybody else in fourth grade.

“Hello? Anybody there?” I asked.

That was when I heard it: a soft, bouncy sound, like a marshmallow dropped on the kitchen floor. I knew there were no marshmallows in the Crypt. Papa said there weren’t any dead bodies, either, even though that was what you were supposed to put in a Crypt. Papa said Congress wanted to bury George Washington here, but Martha wanted the president home with her at Mt. Vernon. But what if George Washington wanted to be buried in the Crypt? What if his ghost had come back to haunt the place? Maybe he waited until all the tourists were gone and the only person left in the Crypt was the girl who forgot where she left her hoodie and he was going to—

That was when I saw it. A ginormous shadow crept up the wall. It was tall and curved, like a ghostly question mark. The shadow quivered in the air. There was a howl, a long, whiny “mrreowow.” It seemed to ask, “Fina Mendoza, what are you doing here?”

“My sweatshirt,” I said, my voice cracking.

The ghost mrreowowed again, seeming to echo, “Sweatshirt?”

It was just a stupid school sweatshirt. If it was lost forever, Gabby would yell at me about being irresponsible, and Papa would make me use my birthday money to buy a new one. That was pretty bad, but was it worse than having the ghost of George Washington mad at me? His face looked so serious on the front of a one dollar bill, like he thought I was wasting money on something stupid. Now he wanted to know why I was in the Crypt.

“I’m sorry,” I whispered to the ghost. “I’m sorry. I’ll just leave now.”

Before I could escape, something moved. It was silent. It was swift. Behind the statue of Caesar Rodney, I saw a swish of something black, like a backpack with feet or a garbage bag with a tail. I opened my mouth to scream, but nothing came out. I told my feet to start running, but they weren’t listening.

I saw a flash of yellow eyes and the flick of a furry tail. What was it? It wasn’t the ghost of George Washington. It was much more real, much more scary. As quickly as the creature appeared, it was gone.

I unstuck my feet and hurried over to look behind Caesar Rodney’s marble boot, just to be sure. What had I just seen? Where did it come from? Where had it gone? Was it real? Or had I imagined the whole thing?

I listened again. This time, I heard squeaky footsteps, rubber-bottomed shoes on the stone floors.

“Still here, kid?”

It was that Capitol policewoman. The one who yelled at me for not taking off my seven jangly bracelets before walking through the metal detector.

“I–I thought I heard something.”

“It’s an old building. You hear lots of things,” she said.

“Like an animal. An angry creature.”

“Ah,” she said, and her voice got lower. “The Demon Cat. You have heard of the Demon Cat, haven’t you?”

I didn’t answer. I hadn’t heard of any Demon Cat and didn’t want to waste my time listening to some stupid story. Besides, the creature I saw was bigger than a cat. Much bigger.

“The rumor is...”

Oh, boy, I thought. Here it comes.

The policewoman leaned in and whispered. “Occasionally, people will see a black cat that swells to the size of a Mini Cooper, eyes glowing, hissing and spitting.”

The creature I saw wasn’t quite the size of a small car, but it was black. “Does it yowl?” I didn’t mean to ask that, but it just popped out of my mouth.

The Capitol policewoman nodded grimly. “It usually makes an appearance right before something really bad happens.”

My heart started to beat loudly. I knew that really bad things happened to people. They had happened to me, to the whole Mendoza family, back in California. Moving to Washington was supposed to get Gabby and me away from all the bad things. I didn’t want to think about really bad things right now. My voice got very quiet. “How bad?”

The policewoman shrugged. “Depends. A lawmaker loses an election.”

I breathed a sigh of relief. Big deal, I thought. I wasn’t a member of Congress. And Papa won his last election by a zillion votes.

“Or bad luck follows you wherever you go,” she said, “like the tail of the Demon Cat.”

I knew I shouldn’t believe her, but I felt a shiver at the top of my neck that traveled down my whole back. The Mendoza family didn’t need any more bad luck.

“Or someone could even die,” she whispered.

I gasped.

“Beware the curse,” she said. “The curse of the Demon Cat of Capitol Hill.”

I slowly backed away from her until I got to one of the stone archways. Forget the sweatshirt! I turned and ran down the long, dark hallway to reach the elevator. I could still hear her voice in my head, saying over and over again, “Beware the curse, the curse of the Demon Cat.”