July 15, Wednesday. Phase of the moon: New.

These are the rituals of the Saul family.

At one P.M., Uncle Peter comes home from his half day at the clinic. He changes into jeans and a T-shirt and heads for his vegetable garden, where a jungle of tomato plants and cucumber vines weigh down their string trellises.

At two P.M., little Teddy comes up the hill from the lake, carrying his fishing pole. But no catch. I have not yet seen him bring home a single fish.

At two-fifteen, Lily’s two girlfriends walk up the hill, carrying bathing suits and beach towels. The taller one-I think her name is Sarah-also brings a radio. Its strange and thumping music now disturbs the otherwise silent afternoon. Their towels spread out on the lawn, the three girls bask in the sun like drowsy felines. Their skin gleams with suntan lotion. Lily sits up and reaches for her bottle of water. As she lifts it to her lips, she suddenly goes still, her gaze on my window. She sees me watching her.

It is not the first time.

Slowly she sets down the water bottle and says something to her two friends. The other girls now sit up and look in my direction. For a moment they stare at me, as I am staring at them. Sarah shuts off the radio. They all rise to their feet, shake out their towels, and come into the house.

A moment later, Lily knocks on my door. She doesn’t wait for an answer but walks uninvited into my room.

“Why do you watch us?” she says.

“I was just looking out the window.”

“You’re looking at us.”

“Because you happen to be there.”

Her gaze falls on my desk. Lying open there is the book my mother gave me when I turned ten years old. Popularly known as the Egyptian Book of the Dead, it is a collection of ancient coffin texts. All the spells and incantations one needs to navigate the afterlife. She moves closer to the book, but hesitates to touch it, as though the pages might burn her fingers.

“Are you interested in death rituals?” I ask.

“It’s just superstition.”

“How do you know unless you’ve tried them?”

“You can actually read these hieroglyphs?”

“My mother taught me. But those are just minor spells. Not the really powerful ones.”

“And what can a powerful spell do?” She looks at me, her gaze so direct and unflinching that I wonder if she is more than she seems. If I’ve underestimated her.

“The most powerful spells,” I tell her, “can bring the dead back to life.”

“You mean, like in The Mummy?” She laughs.

I hear more giggles behind me and turn to see her two friends standing in the doorway. They’ve been eavesdropping, and they look at me with disdain. I am clearly the weirdest boy they have ever met. They have no idea how different I really am.

Lily closes the Book of the Dead. “Let’s go swimming, girls,” she says, and walks out of the room, trailing the sweet scent of her suntan lotion.

Through my window, I watch them head down the hill, toward the lake. The house is now quiet.

I go into Lily’s room. From her hairbrush, I pull off long brown strands of hair and slip them into my pocket. I uncap the lotions and creams on her dresser and sniff them; each scent brings with it the flash of a memory: Lily at the breakfast table. Lily sitting beside me in the car. I open her drawers, her closet, and touch her clothes. Clothes that any American teenager might wear. She’s just a girl after all, nothing more. But she needs watching.

It’s what I do best.

Siena , Italy . August.

Lily Saul bolted awake, straight from a deep sleep, and lay gasping among twisted bedsheets. The amber light of late afternoon glowed through the crack between the partially closed wooden shutters. In the gloom above her bed, a fly buzzed, circling in anticipation of a taste of her damp flesh. Her fear. She sat up on the thin mattress, shoved back tangled hair, and massaged her head as her heartbeat gradually slowed. Sweat trickled from her armpits, soaking into her T-shirt. She had managed to sleep through the worst heat of the afternoon, but the room still felt suffocating, the air thick enough to smother her. I can’t keep living this way forever, she thought, or I’ll go insane.

Maybe I’m already insane.

She rose from the bed and crossed to the window. Even the ceramic tiles beneath her feet radiated heat. Throwing open the shutters, she gazed across the tiny piazza, at buildings baking like stone ovens in the sun. A golden haze leafed domes and rooftops in umber. The summer heat had driven the sensible locals of Siena indoors; only the tourists would be out now, wandering wide-eyed through narrow alleys, huffing and sweating their way up the steep incline to the basilica or posing for photographs on the Piazza del Campo, their shoe soles melting and tacky on the scorching brickwork: all the usual tourist things that she herself had done when she’d first arrived in Siena, before she’d settled into the rhythms of the natives, before the heat of August had closed in on this medieval city.

Below her window, on the piazzetta, not a soul moved. But as she was turning away, she spied a twitch of motion in the shadow of a doorway. She went very still, her gaze fixed on the spot. I can’t see him. Can he see me? Then the inhabitant sheltering in that doorway emerged from its hiding place, trotted across the piazzetta, and vanished.

Only a dog.

With a laugh, she turned from the window. Not every shadow hid a monster. But some did. Some shadows follow you, threaten you, wherever you go.

In her tiny bathroom she splashed lukewarm water on her face, pulled back her dark hair in a ponytail. She did not waste time with makeup; over the past year, she had shed any habits that slowed her down. She lived out of one small suitcase plus a backpack, owned only two pairs of shoes, her sandals and sneakers. Jeans and T-shirts and sweaters took her from the heat of summer to the sleet of winter. When you got right down to it, survival was all a matter of layering, whether it was with clothes or emotional defenses. Keep out the elements, ward off attachments.

Stay safe.

She grabbed her backpack and stepped out of the room into the gloomy hallway. There she paused, as she always did, and inserted a torn bit of cardboard matchstick into the lower jamb as she closed the door and locked it. Not that the ancient lock would keep anyone out. Like the building, it was probably centuries old.

Bracing herself for the heat, she walked outside, into the piazzetta. She paused, scanning the deserted space. It was still too early for most locals to be out and about, but in another hour or so, they would stir from their meal-induced naps and start back to their shops, their offices. Lily still had some time to herself before Giorgio expected her back at work. It was a chance to walk and clear away the cobwebs, to visit her favorite haunts in her favorite city. She had been in Siena only three months, and already she could feel the town slipping away from her. Soon she’d have to leave it, as she’d left every other place she’d loved.

I have stayed here too long already.

She walked through the piazzetta and headed up the narrow alley leading to Via di Fontebranda. Her route took her toward the town’s ancient fountain house, past buildings that once housed medieval craftsmen and later slaughterhouses. The Fontebranda was a Siena landmark once celebrated by Dante, and its waters were still clear, still inviting, even after the passage of centuries. She had walked here once beneath the full moon. According to legend, that was when werewolves came to bathe in the waters, just before transforming back to their human forms. That night, she’d glimpsed no werewolves, only drunken tourists. Perhaps they were one and the same.