Harold, I can't find Serena. She went out with Lilith earlier and she hasn't come back. She's not responding to my texts and Lilith's mums phone seems to be off. I'm going to Lilith's house to check if she's there. Tell me if you hear anything.

I visited Lilith and she's not telling me anything. She said they never met up but she thought she did. "Turns out it wasn't her" What does it mean? I kept on asking and she wouldn't budge. She doesn't know where she is and won't tell me what happened. I recommended she text Serena about it and she agreed. She started muttering and decided to write a letter and I'm not sure if this is correct, but I heard her say "just in case that imposter finds out." I'm not sure what's happening to Lilith, but I'll talk to her mum once she replies. She sent the letter to my mother's house. Could you please go grab it?

I'm getting worried for our daughter.

Harold made it to Clementine’s mother’s house in eight minutes. He’d read the message twice at the red light on Marlowe Street, and a third time in the driveway, trying ti make sense of it. Turns out it wasn’t her. That imposter. Clementine’s mother, Odette, opened the door before he had time to knock. She was still in her dressing gown, though it was past four, and she held a cream envelope.

“Someone slid it through the letterbox about twenty minutes ago. I didn’t see who.”

“Lilith’s handwriting?”

“I wouldn’t know Lilith’s handwriting.” Odette handed it over. “But it’s addressed to Clem, Harold, and you’re not Clem.”

“She asked me to fetch it. She’ll want it read straight away.”

Odette’s eyes narrowed, but she stepped aside. “Then read it in the kitchen.”

The envelope was sealed with a strip of tape rather than gummed down, and the tape had been pressed so hard it had torn the paper beneath. The handwriting on the front was cramped and slanted, the letters leaning on each other like old men. Harold slid a thumb under the flap. There was a single sheet inside, folded in thirds.

Mrs. Claret,

If you are reading this, then I did not get the chance to say it aloud, and I am sorry for that.

I did meet someone today. I thought it was Serena. She had the same coat, same laugh, same nervous tics, she knew all the stupid little inside jokes that only Serena would know. We walked to the old greenhouse behind Pennywhistle Lane because she said she had something to show me.

I don't know what it was, but it wasn't her. I left her there, and I don’t know where the real Serena is.

Do not trust any message from Serena’s phone until you have heard her voice. Ask her about the thing at the lake. Only the real Serena will know the answer, and I will not write it here.

I’m sorry. I’m so sorry.

Lilith

Harold read it a second time, and then a third. Behind him the kettle clicked off and Odette moved silently to pour the tea.

“Well?” she said at last.

He turned the page over. On the back, in a different pen and a much shakier hand, someone had added a final line:

She’s still wearing the coat. Look for the coat.

“Odette,” Harold said carefully, “when did you say this came through the letterbox?”

“Twenty minutes ago. Why?”

He held up the page. The ink on that last line was still glossy, not quite dry. Somewhere outside, a gate clicked shut.

The street lay empty as Harold tore out the front door, lined with parked cars and clipped hedges. But at the far end, just turning the corner toward Pennywhistle Lane, he caught a flash of something deep red: the coat. His phone buzzed in his hand as he began to give chase. He paused. It was a message from Clementine.

Harold, Serena just texted me. She says she’s fine and she’s coming home I'm going to get her from the bus stop. Did you get the letter?