Just because you can’t see them doesn’t mean they aren’t there.

I’m sitting in History class when I feel the tap-tap-tap on my shoulder, like drops of rain. Some people call it intuition, others second sight. That tickle at the edge of your senses, telling you there’s something more.

This isn’t the first time I’ve felt it—not by a long shot. Not even the first time I’ve felt it here at my school. I’ve tried to ignore it—I always do—but it’s no use. It wears away at my focus, and I know the only way to make it stop is to give in. Go and see for myself.

From across the room, Jacob catches my eye and shakes his head. He can’t feel that tap-tap-tap, but he knows me well enough to know when I do.

I shift in my seat, forcing myself to focus on the front of the classroom. Mr. Meyer is valiantly trying to teach, despite the fact it’s the last week of school before summer vacation.

“… Toward the end of the Vietnam War in 1975, US troops …” my teacher drones on. Nobody can sit still, let alone pay attention. Derek and Will are sleeping with their eyes open, Matt is working on his latest paper football. Alice and Melanie are making a list.

Alice and Melanie are popular kids.

You can tell because they look like copies—same shiny hair, same perfect teeth, same painted nails—where I’m all elbows and knees, round cheeks, and curly brown hair. I don’t even own nail polish.

I know you’re supposed to want to be one of the popular kids, but the truth is, I never have. It just seems like it would be exhausting, trying to keep up with all the rules. Smile, but not too wide. Laugh, but not too loud. Wear the right clothes, play the right sports, care about things, but never care too much.

(Jacob and I have rules, too, but those are different.)

As if on cue, Jacob stands up and makes his way toward Melanie’s desk. He could be a popular kid, I think, with his floppy blond hair, bright blue eyes, and good humor.

He shoots me a devilish look before perching on the edge of her desk.

He could be, but there’s just one problem.

Jacob’s dead.

“‘Things we need for movie night … ’ ” he reads aloud from Melanie’s paper. But I’m the only one who can hear him. Melanie folds another sheet, an invitation—I can tell by the capital letters, the pink pen—and reaches forward to pass it to Jenna, who sits in front of her. As Melanie does this, her hand goes straight through Jacob’s chest.

He looks down, as if offended, then hops off the desk.

Tap-tap-tap goes the feeling in my head, like a whisper I can’t quite hear. Impatient, I check the clock on the wall, waiting for the lunch bell.

Jacob meanders over to Alice’s desk next, examining the many multicolored pens she keeps lined up across the top. He leans in close and gingerly brings one of his fingers to the pens, all his focus narrowed on the nearest one as he pokes it.

But the pen doesn’t move.

In the movies, poltergeists can lift televisions and slide beds across the floor. But the truth is, it takes a lot of spirit power for a ghost to reach across the Veil—the curtain between their world and ours. And the ghosts that do have that kind of strength, they tend to be really old and not very nice. The living may take strength from love and hope, but the dead grow strong on darker things. On pain and anger and regret.

Jacob furrows his brow as he tries—and fails—to flick Matt’s paper football.

I’m glad he’s not made of all that stuff.

I don’t actually know how long Jacob’s been dead (I think the word quietly, because I know he doesn’t like it). It can’t have been that long, since there’s nothing retro about him—he’s got on a superhero T-shirt, dark jeans, and high-tops—but he doesn’t talk about what happened, and I don’t ask. Friends deserve a little privacy—even if he can read my mind. I can’t read his, but all things considered, I would rather be alive and not psychic than psychic and a ghost.

He looks up at the word ghost and clears his throat. “I prefer the phrase ‘corporeally challenged.’ ”

I roll my eyes because he knows I don’t like it when he reads my mind without asking. Yes, it’s a weird side effect of our relationship, but come on. Boundaries!

“It’s not my fault you think so loud,” Jacob replies with a smirk.

I snort, and a few students glance my way. I sink lower in my chair, my sneakers knocking against my book bag on the floor. The invitation Melanie passed to Jenna makes its way around the room. It doesn’t stop at my desk. I don’t mind.

Summer is almost here, and that means fresh air and sunshine and books to read for fun. It means the annual family trek down to the rented beach house on Long Island so Mom and Dad can work on their next book.

But most of all, it means no hauntings.

I don’t know what it is about the beach house—maybe the fact that it’s so new, or the way it sits on a calm stretch of shore—but there seem to be far fewer ghosts down there than here in upstate New York. Which means that as soon as school’s out, I get six full weeks of sun and sand and good nights’ sleep.

Six weeks without the tap-tap-tap of restless spirits.

Six weeks of feeling almost normal.

I can’t wait for the break.

I can’t wait … and yet, the moment the bell rings, I’m up, backpack on one shoulder and purple camera strap on the other, letting my feet carry me toward that persistent tap-tap-tap.

“Crazy idea,” says Jacob, falling into step beside me, “but we could just go to lunch.”

It’s Meat Loaf Thursday, I think, careful not to answer out loud. I’d rather face the ghosts.

“Hey, now,” he says. But we both know Jacob’s not a normal ghost, just like I’m not a normal girl. Not anymore. There was an accident. A bike. A frozen river. Long story short, he saved my life.

“Yeah, I’m practically a superhero,” Jacob says, right before a locker swings open in his face. I wince, but he passes straight through the door. It’s not that I forget what Jacob is—it’s pretty hard to forget when your best friend is invisible to everyone else. But it’s amazing what you can get accustomed to.

And it says something that the fact that Jacob’s been haunting me for the past year isn’t even the strangest part of my life.

We hit the split in the hall. Left goes to the cafeteria. Right goes to the stairs.

“Last chance for normal,” Jacob warns, but he’s got that crooked grin when he says it. We both know we passed normal a long time ago.

We go right.

Down the stairs and along another hall, against the flow of lunchtime traffic, and with each turn, the tap-tap-tap gets stronger, turning into a pull, like a rope. I don’t even have to think about where to go. In fact, it’s easier if I stop thinking and just let it reel me in.

It draws me to the doors of the auditorium. Jacob shoves his hands in his pockets and mutters something about bad ideas, and I remind him he didn’t have to come, even though I’m glad he did.

“Ninth rule of friendship,” he says, “ghost-watching is a two-person sport.”

“That it is,” I say, snapping the cap off my camera lens. It’s a clunky old beast, this camera, a manual with a busted viewfinder and black-and-white film, hanging off my shoulder on its thick purple strap.