“He could also last another twenty years.”

“You mean, he might still be doing bad things?” she asked softly.

I stood there, for a moment unable to answer. Mindy had died thirty-five years ago, so the bad man had to be middle-aged, at least. But that didn’t mean he’d retired as a murderer.

“Look, I thought about calling the police,” I said. “But what can I tell them? That I saw the ghosts of his victims in his yard?”

Mindy stared at the ground. She was only eleven, and didn’t know about evidence and probable cause. She just knew she was afraid.

“The police didn’t do anything back then, either,” she said.

“I’m sure they tried.”

She looked up at me, the usual sadness showing in her eyes. The echoes of what had happened thirty-five years ago were wound up inside her, as inescapable as death. The only way for Mindy to get over her fear was for someone to end the bad man.

And I could walk through walls.

* * *

The River Vaitarna was wild and angry later that night, full of cold wet things. But it knew exactly where to take me.

As my feet touched the ground, I dropped my gaze to the street, not wanting to see those five little girls standing among the gnarled trees. More important, I didn’t want them seeing me, connecting with me. I was already breaking my promise to Yama to stay away.

This wasn’t my first time taking the river without him by my side. I’d been practicing all week, midnight jaunts to my old middle school or Mom’s work. But it was strange being here, a place that really made me nervous, without him.

I walked to the next corner and checked the street sign: Hillier Lane. My phone didn’t work in the flipside, but I pulled a folded piece of paper from my back pocket. I hadn’t told Mindy where I was going, but she’d watched me print out the street map.

Eyes on the paper, I made a left turn, walked another block, and turned left again, circling toward the bad man’s backyard. But the streets weren’t a neat grid, and the alleyways didn’t have signs. I wandered for a few minutes, half-lost. It was after one a.m., and there were no people around, no cars . . .

Just a cat, its green eyes peering at me from down the street.

“Is that you?”

The cat blinked. I’d seen it a week ago, when Yama and I had first taken the river to my mother’s old house.

It watched me approach with vague interest, then turned and trotted away. I broke into a jog, trying to keep pace without scaring it.

The cat turned from the main street into a small back lane, like the one behind our house in San Diego, but messier. There were garbage bins lining the path, a set of abandoned dining chairs. Grass sprouted from backyards, tall and wild.

The cat finally slipped away through a gap in a wooden fence, and I couldn’t follow. But I had to be close. I walked along the alley, checking both sides until I was staring at a house that looked familiar. It had the same small A-frame as the bad man’s bungalow, the same thick coat of stucco. There were no ghostly little girls in the backyard, but I was glad for that.

I stood there, letting my breathing slow. I’d learned tonight that to walk through solid objects, I had to stay focused. The last thing I wanted was to get trapped in a panic on the wrong side of the bad man’s walls.

As I passed through his backyard fence, its chain links tugged at me, but gave way with little pops, like icicles breaking. The bad man’s windows were all dark, and when I climbed the steps to the back door, I heard nothing from inside.

I didn’t have a plan, just a vague idea of finding something to tell the police about. But I had no excuse not to try. Here on the flipside I was invisible, invulnerable to anything a living person could do.

I took another slow breath and passed through his back door, out of the moonlight and into the darkness inside.

It was dead silent in the house. The air seemed thick, the smell of rust growing until it was a taste in my mouth. I took slow steps forward, reaching my hands out in the blackness. Then I realized that the windows were covered with newspaper.

“Nothing creepy about that,” I murmured, and stood still, willing my eyes to adjust. The thought of stumbling into something in those shadows made my skin crawl.

The flipside had its own glow, gray and soft. A utility room gradually came into focus around me, the sort of place where you’d change your shoes before going into the rest of the house. Shelves of paint cans and garden tools, a few bags of soil piled in one corner. Another door stood before me. After a calming breath, I passed through it without a hitch.

Here in the kitchen moonlight flooded through the windows, and it was cheery compared to the blacked-out room behind me. The sink was spotless, a row of water glasses sparkling in a drying rack. The tiled floor looked freshly mopped.

An ordinary kitchen, as far as I could see. Except for the freezer, which was too big.

White and shiny, long as a coffin, it took up a whole wall. As I stared at it, the compressor popped on, setting the floor rumbling beneath my feet. It would be no problem to fit an adult inside, much less a child.

But my body was back in San Diego, so I was stuck here on the flipside, unable to open the door. All I could do was pass through things.

I stepped closer, placed a hand on the freezer’s cool metal skin. Its motor trembled beneath my palm. I closed my eyes, letting them adjust to darkness again, counting slowly to a hundred.

Eyes still closed, I bent over the gently humming machine, willing myself through solid metal. Cold air touched my nose, then spread across my cheeks and forehead, as if I were dipping my face into water.

The hardest part was opening my eyes again, not knowing what would be there, inches from my face. When finally I did, I saw something in the gray light of the flipside, lumpy and formless. . . .

Peas. Frozen peas in a bag.

There were also gray tubs of ice cream, plastic-wrapped steaks, and a pile of gel packs, the kind my father had used after his jogging injury a few years ago.

The bad man had bad knees, it seemed.

I pulled myself back out, and stood there shivering in the pale spotlessness of the kitchen. The freezer looked solid again in front of me, much less menacing now.

What if this wasn’t even the right house?

Next to the kitchen was a living room dominated by a big TV. The couch was old and musty-looking, but very neat, the pillows plumped and fat. No pictures of family, no chairs for guests, just a folding tray for eating in front of the TV.

Past the living room was a hallway. The floorboards looked like they would creak when I stepped on them, but here on the flipside I was as weightless as a ghost. The hallway took me past a bathroom, a linen closet slightly ajar, and two closed doors, then finally to the bungalow’s entrance.

I pressed my ear against the two interior doors. No sound from either.

I picked one, and passed into a study crowded with an old oak desk. A row of fancy pens lay on it, perfectly aligned with the edges. The whole house was obsessively tidy, nothing like the chamber of horrors I had imagined. No chains and hooks hanging from the ceiling, not a layer of grime in sight.

The desk had four drawers, and the shelves on the back wall were full of binders with neat labels. They didn’t seem to be full of evidence of the bad man’s murders, unless “State Taxes” meant more than it said. In any case, there was no way to open them. To do that, I would have to travel up here in the flesh.

My nerves were fading into annoyance. I’d been an idiot, thinking that he would leave evidence of his crimes lying around. This was a man who’d gotten away with murder for decades.

The desk faced out the front windows of the house, and I could glimpse the gnarled trees in the yard. Among them stood the little ghost girls, staring back at me. My gaze shied away, my breath catching.

Then I saw it on the desk—a phone bill. I stared at it, memorizing the bad man’s name and phone number, trying not to think of the little girls outside.

There was only one more door to check out. I slipped back into the hallway and faced it.

It had to be his bedroom. Sleeping inside was the man who had killed Mindy and changed my mother’s life, who was the reason she’d been afraid every minute of my childhood.

My nerves were back. But at least I could finally answer Mindy’s question about how old he was, how close to death. I willed the door into transparency and stepped through.

It was darker in here, the heavy curtains drawn. A large bed sat nestled against the windows, full of a formless lump beneath gray blankets. When I listened, I could hear him breathing.

He didn’t sound healthy. A rumble hid somewhere in his chest, something liquid fluttering with every exhalation. On a bedside table was a row of pill bottles, lined up as neatly as the rest of his possessions.

I knelt to read their labels: Pradaxa, Marplan, the made-up names of drugs.

Then I saw, inches from my face, a hand sticking out from beneath the blanket, motionless and pale. It was spotted, wrinkled. The hand of a very old man, or a very ill one.

I wondered what would happen if he died right now in his sleep. Would I see his spirit emerge into the flipside? Where would I guide him, grim reaper that I was?

I turned away from the protruding hand, stood up. The closet was open, full of neatly hanging shirts, shoes lined up on a rack. There was nothing else to check in the room. Unless he kept something hidden under his bed . . .

I took a slow, shuddery breath. Beneath my own bed had always been the scariest place in any house for me, more claustrophobic than any closet.

But it was the last place I had to look for evidence. I knelt, my palms on the floor, and lowered myself, trying not to imagine anything peering back at me from the shadows.

At first I saw nothing but a smooth expanse of floorboards extending into dark gray shadows. No dust bunnies, no discarded tissues. Tidy as always. But then metal glinted deep in the gloom. The glimmer of reflected moonlight was curved, like a smile.

I reminded myself that I was invisible, invulnerable, that ghosts were afraid of me. I leaned on an elbow and reached into the shadows.

My fingers brushed a metal surface, cool and smooth. I stretched a little farther—my hand found a sharp edge, and followed it to a wooden cylinder mounted into the metal.

When I realized what the object was, I jerked my hand back.

A shovel. He slept with a shovel underneath his bed.

I lay there for a long moment, trying to remember exactly what I’d seen in his front yard. Five girls and five gnarled little trees?

Raising myself up to the window ledge, I peeked beneath the curtains. The five girls stood there in his front yard, next to six little trees. The numbers didn’t match.

What if the extra tree was for Mindy? He’d buried her in her own backyard, my mother had said. But why had she been special?

I stared through the window, trying to imagine the front yard before those trees, before the new houses had been built across the street. And, just as it had in the playground, time began to ripple and rewind. The rest of the street was chaos, a churn of motion and construction, people moving in and out, but the old man’s yard hardly changed, the grass pulsing with the seasons. Then suddenly one of the trees disappeared along with its ghost, then another, and another, the bad man’s deadly career reversing before my eyes.

Finally only one tree remained, the one in the middle of the yard. No ghost stood next to it. The little girls were all gone.

Mindy had been his first. Because she had lived nearby.

I dropped my gaze to the floor, rubbing my eyes, blinking away the vision and trying not to hear the wheezy rattle of the bad man’s breathing.

When I opened my eyes and looked out the window again, the present had returned. But the girls shifted a little under my gaze, as if they’d felt me dredging up the past. The one in overalls was staring back at me, her head cocked to one side like a puppy’s.

I remembered Yama’s warnings, and pulled away from the window. As I did, my shoulder brushed those motionless, outstretched fingers. The faintest spark passed between us, like when my cheek had touched Agent Reyes’s.