In the car on the way back, neither of them spoke until they reached the New Riverby reservoir, where the valley was filled with glittering silver to the horizon. The water level was low, after the month-long heatwave. Harper could see the stubby outlines of the remains of walls at the exposed edge of the lake, and in the centre the tip of the old Selverton Church tower, black and pointed like a blade pushing up through the surface.

To Harper, the inside of the car seemed a much calmer place without the twins. She relished the silence, the sense of peace. As the car travelled over the viaduct, Patrick lifted his head from where it rested on the passenger window. For a few moments he watched the landscape slip by.

“I should never have left the babies with her. They’re not safe.”

“I don’t think you need to worry,” said Harper. “They have procedures. Didn’t the doctor say that Morgan and Riley wouldn’t be left alone with Lauren, even for a moment, until they could be sure everything would be fine?”

“You saw what she was like.”

“Yes,” said Harper. “But they’re going to help her.”

“She’s not fit to look after them. I should have brought them home.”

“If you’d done that, they wouldn’t be able to treat her at Hope. She has to have the babies with her for that. Believe me,” said Harper, “you don’t want her to be transferred to the general ward. Hope Park might be a bit like a prison but the alternative is … well. You don’t want to know.”

“Why?” said Patrick. “What’s it like?”

She’d only had to go into the Selver General unit once, for an interview. There’d been a confession by an inmate to a historic murder case. Inmate, she chided herself. She meant patient, of course, though the unit was worse than any prison she’d been inside. For Harper it was always the small details that held the most power: the porcelain-and-meat sound of teeth knocked askew on metal bed rails; the pop of ligaments stretched to breaking as arms were expertly twisted back in restraint; the moment, hours later in her own bathroom, when she reached forward to rub at the mirror, thinking it was dirty, but no, there on her face and over her white shirt a light splattering of pink, a man’s saliva mixed with his blood, which must have sprayed over her as he was carried past, choking.

“Don’t think about that now,” said Harper, wondering, if it came to it, what favours she could pull in to keep Lauren away from that place. “It won’t happen. She’ll come around. She loves those boys.”

“Yeah,” said Patrick, sounding lost, “I thought she did, too.”

Patrick directed Harper to drop him off at his sister’s house. She pulled up outside and turned off the engine.