Then it swung back, pushing her off the linen basket. She landed heavily on her left arm outside the spare room. The hatch had split her skin on three fingers. Little droplets of blood began to bubble. She climbed back on to the basket, reached up with both hands and pulled herself into the loft.

The boxes were exactly where she’d left them. 2.56pm. Less than four minutes to respond to the challenge. She opened the first of six square storage boxes and quickly set it aside. The second and third weren’t it either. But there in the fourth was the blue file she needed.

She rested it on her knee. The name on the front was written in very neat handwriting. It was the first file she had ever produced. She’d prepared it with the care of a new mother. Seraphine Walker.

Bloom riffled through the pages for the pathologist’s report. She skimmed the page. How had they identified Seraphine’s teenage body? Bloom had assumed they’d looked at her dental records. Trains at speed do unspeakable things to the human body. But they hadn’t checked. Seraphine had left a note for her mother telling her what she was planning to do and where. The body had been wearing Seraphine’s clothes, a watch engraved with her name and a necklace borrowed that very day from her mother. This had been deemed sufficient evidence.

Bloom stared into the dark recesses of her parents’ loft. This was crazy. How could a fourteen-year-old girl find another girl of similar height, weight and hair colour, convince her to swap clothes and jewellery, take a bus to a random town, walk a mile and a half to a farm road and then …? But this was Seraphine. She had the ability to fool people, to lure them into her web.

I can’t be normal. And I don’t want to be a monster.

Her challenge was more than just the Trolley Problem. It was very specific. She was being asked to choose between the life of one normal person, Sarah, or the lives of three psychopaths, Grayson, Stuart and Lana. Jane was a red herring. She came with Lana.

When working with Seraphine, Bloom had stressed that the young girl could choose who she wanted to be. That she didn’t need to be defined by a label. That a psychopath’s life was just as valuable as any other. This challenge was predicated on that very principle.

The alarm on her phone began to jingle. It was 2.59pm.

55

Jameson stood at the doorway to Sarah’s room, one hand on the frame. He’d been here just a few hours ago. He remembered purple velvet curtains, a damask chaise longue at the end of the bed, a neatly organized wooden desk and bedside tables, the smart king-sized bed. The room he saw now bore no resemblance to this memory.