At least out here I could think and feel and speak without watching my every word, my every expression, my every mood.

I could be me, without fearing that I would slip up.

“Come on,” I said to Petra. Her buggy was in the boot of the car, and I opened it up and slid her in, clipping the rain cover over her. “Let’s go for a walk.”

“Me walk!” Petra shouted, pushing her hands against the plastic, but I shook my head.

“No, honey, it’s too wet, and you’ve not got your waterproofs on. You stay snug and dry in there.”

“Puggle!” Petra said, pointing through the plastic. “Jumpin muggy puggle!” It took me a minute to realize what she was saying, but then I followed her gaze to the huge pool of water that had collected on the gravel in the old stable yard, and understanding clicked.

Muddy puddles. She wanted to jump in muddy puddles.

“Oh! Like Peppa Pig, you mean?”

She nodded vigorously.

“You haven’t got your Wellies on, but look—”

I began to walk faster, and then jog, and then with an enormous splash, I ran, buggy and all, through the puddle, feeling the water spray up all around us and patter down on my anorak and the buggy’s rain cover.

Petra screamed with laughter.

“Again! More puggle!”

There was another puddle farther around the side of the house and obligingly I ran through that too, and then another on the graveled path down towards the shrubbery.

By the time we reached the kitchen garden, I was soaked and laughing, but also getting surprisingly cold, and the house was beginning to seem a little bit more welcoming. Full of cameras and malfunctioning tech it might be, but at least it was warm and dry, and out here my fears of the night before seemed not just silly, but laughable.

“Puggle!” Petra shouted, bouncing up and down underneath her clips. “More puggle!”

But I shook my head, laughing too.

“No, that’s enough, sweetie, I’m wet! Look!” I came round to stand in front of her, showing her my soaked jeans, and she laughed again, her little face scrunched up and distorted through the crumpled plastic.

“Woan wet!”

Woan. It was the first time she had made an attempt at my name, and I felt my heart contract with love, and a kind of sadness too—for everything I could not tell her.

“Yes!” I said, and there was a lump in my throat, but my smile was real. “Yes, Rowan is wet!”

It was as I was turning the buggy around to start the climb back up to the house that I realized how far we had come—almost all the way down the path that led to the poison garden. I glanced over my shoulder at the garden as I began to push the buggy up the steep brick path—and then stopped.

For something had changed since my last visit.

Something was missing.

It took me a minute to put my finger on it—and then I realized. The string tying up the gate had gone.

“Just a second, Petra,” I said, and ignoring her protests of “More puggles!” I put the brake on the buggy and ran back down the path to the iron gate, the gate where Dr. Grant had been photographed, standing proudly before his research playground, so many years ago, the gate I had tied up securely, in a knot too high for little hands to reach.

The thick white catering string had gone. Not just untied, or snipped and thrown aside, but gone completely.

Someone had undone my careful precautions.

But who? And why?

The thought nagged at me as I walked slowly back up the hill to where Petra was still sitting, growing increasingly fretful, and it continued to nag as I pushed the buggy laboriously back up the hill, to where the house was waiting.

* * *

By the time I reached the front door, Petra was cross and grizzling, and looking at my watch I saw that it was long past her snack time, and in fact getting on for lunch. The buggy’s wheels were caked with mud, but since I had left the key to the utility room on the inside, I had no option other than the front door, so at last I got her out of the buggy, folded it awkwardly with one hand, holding Petra against my hip with the other to stop her from running off in search of more puddles, and left it in the porch. Then I pressed my thumb to the white glowing panel, and stood back as the door swung silently open.

The smell of frying bacon hit me instantly.

“Hello?”

I put Petra down cautiously on the bottom stair, shut the door, and prized off my muddy boots.

“Hello? Who’s there?”

“Oh, it’s you.” The voice was Rhiannon’s, and as I picked up Petra and began to make my way through to the kitchen, she came out of the doorway, holding a dripping bacon sandwich in one hand. She looked terrible, green around the gills and with dark shadows under her eyes as if she’d slept even less than me.

“Oh, you’re back,” I said unnecessarily, and she rolled her eyes and stalked past me to the stairs, taking a great bite of sandwich as she did.

“Hey,” I called after her as a blob of brown sauce hit the tiled floor with a splat. “Hey! Take a plate, can’t you?”

But she was already gone, loping up the stairs towards her room.

As she passed though I caught a whiff of something else—low and masked by the scent of bacon, but so odd and out of place, and yet so familiar, that it stopped me in my tracks.

It was a sweet, slightly rotten smell that jerked me sharply back to my own teenage years, though it still took me a minute to pin down. When the association finally clicked into place, though, I was certain—it was the cherry-ripe reek of cheap alcohol, leaching out of someone’s skin, the morning after it’s been drunk.

Shit.

Shit.

Part of me wanted to mutter that it was none of my business—that I was a nanny and had been hired for my expertise with younger children—that I had no experience with teenagers, and no idea of what Sandra and Bill would consider appropriate. Did fourteen-year-olds drink now? Was that considered okay?

But the other part of me knew that I was in loco parentis here. Whether or not Sandra would be concerned, I had seen enough to worry me. And there were plenty of red flags about Rhiannon’s behavior. But the question was, what should I do about it. What could I do about it?

The questions nagged at me as I made myself and Petra a sandwich and then put her down for her nap. I could go and question Rhiannon—but I was pretty sure she’d have a ready excuse, assuming she deigned to talk to me.

Then I remembered. Cass. If nothing else, she would be able to explain the exact sequence of the night’s events to me, and maybe give me an idea of whether I was ascribing more to this than I should. A bunch of fourteen-year-old girls at a birthday party . . . it wasn’t impossible Cass had supplied some alcopops herself, and Rhiannon had just drunk more than her fair share.

Cass’s return text was still in my list of messages, and I scrolled down until I found it, and pulled out the number. Then I waited while it rang.

“Yup?” The voice was rough, and Scottish, and very male.

I blinked, looked at the phone to check I had dialed the right number, and then put it back to my ear.

“Hello?” I said, cautiously. “Who is this?”

“I’m Craig,” said the voice. It didn’t sound like a kid, the voice had to be someone at least twenty, maybe older. And it definitely didn’t sound like anyone’s mum, or dad for that matter. “More to the fucking point, who the fuck are you?”