“Put it through,” she said. “And think kindly of me at home time.”

“I always think kindly of you. We’ve got a mobile number for this one. Young lass shouted for help and gave a garbled address, then hung up. You’re about six minutes from the street we’ve pinned the call to.”

“Right-o, thanks. Speak to you in a bit.” She acknowledged the job as the screen started to bleep, and then used hands-free to call Rosie.

“How do,” Rosie said, sounding uncharacteristically harried. “If this dopey pillock in front of me slams on to read another road sign, I’m having him for reckless endangerment. Where are you? Because at this rate I might miss you.”

“Worry not, I’m going to be late anyway,” Jem said, rather touched by how stressed Rosie was. “I’m making a detour to an abandoned call first. It’s only on Mansfield Street, so I shouldn’t be too long.”

“Mansfield Street? Is that off Dunnock?”

Jem adjusted the satnav to widen the view. “Yes, it’s the one with the big detacheds on it. There’s a nursing home at the bottom end.”

“And a beautiful patch of wasteland opposite,” Rosie added. “It’s very scenic after dark or in a pea-soup fog.”

Jem laughed and turned onto Dunnock, muting her sirens as she decelerated for a speed bump. Dusk was well established, helped along by the ever-present rain and a thin shrouding of mist. “In which case, we have the perfect conditions. And it’s got to be prettier than the B&Q car park.”

“Not to mention closer.” Rosie swore, and there was a distinct squeal of brakes in the background. Jem tensed, waiting for the crunch of metal on metal, but all she heard was Rosie slap something hard and mutter something very impolite.

“Ooh, are you going to arrest him?” Jem asked.

“No, I am not,” Rosie said through teeth that were audibly gritted. “I am going to sit calmly at this red light and tell my lot that I’m coming to help you with access or something. I shall see you in three.”

“Okay, great,” Jem said, delighted to have her company. “Bit of luck, we’ll be done before the brews go cold.”