‘It’s me. I’m on your side.’ She can feel the heat of his skin, imagine the sweating palms. He jerks his fists away. He might find it easier to tell the truth to Martin than to her, but Martin would probably turn this into a joke. She leans closer. ‘When a child in a family goes missing, the suspects are the people closest to the family, relatives and trusted friends. When he works out our friendship with Eve’s family, that safety officer Mr Richards told me about could put two and two together and come up with an answer that’ll do, even if it’s wrong. You know what police do to us, people like us. They could make you out to be dangerous.’

Blake looks away, bored by the speech or pretending to be.

Then she says it, she has to. ‘They might even think you’ve got something to do with Sorrel’s disappearance.’

She’s lost him. She knows that as soon as he turns away and wrenches the door open. He scrambles out and starts running; for a moment it looks like he’ll continue running down the street but at the last second he swerves into Eve’s drive and disappears.

A minute later a car follows him in, Melly driving Paul’s car very slowly.

It’s cold now, but sweat is trickling down her back. Stupidly handled. Martin might have done better after all. Blake’s school rucksack is in the footwell where he dumped it; she picks it up, hesitates, then tips it out on the seat. The books tumble out first, a dog-eared exercise book, a geography textbook, pens, then several empty packets of crisps followed by a snowstorm of sweet papers. The empty bag feels heavier than it normally does. She shakes again but nothing further falls out and then she remembers. Blake had been thrilled when he unwrapped this rucksack, four Christmases ago. It was a copy of Martin’s, made for camping expeditions, replete with flaps and hidden pockets. Martin had showed him the zip under the rectangle of thick plastic lining the base of the bag; she’d been resigned to the thought of the sweets he would stash in there. Now she pushes her fingers into the space encountering, as she knew she would, a slim shape, roughly bundled in toilet paper to stop it sliding around.