Rosie nodded and battered the cylinder against the glass. A fine pattern of cracks appeared in the first pane, and she grunted with the effort, hefting the cylinder for another attempt. She had taken in smoke as well; her chest was heaving, and her eyes were red-raw and streaming.

“Ava, help me move Chloe into the corner,” Jem said. Wisps of smoke were beginning to eddy around the doorframe, and the carpet seemed to undulate as something collapsed on a lower storey. She didn’t want the girls in the middle of the room. She had been in several burned-out buildings where the centre of the floor had been the first thing to fall.

“Almost there,” Rosie yelled, as Jem sat Chloe by the wall and ripped her radio from her belt. Ignoring the priority button, she hit the open channel and shouted over the din of Rosie smacking the cylinder into the glass again.

“I need urgent backup to five Mansfield Street, Stamford. House fire with four trapped on the top floor.” She had to stop to get her breathing back under control. “We’re trying to break a window—”

Ryan’s voice cut across her. “Jem? Are you trapped?”

“Yes,” she said, surprised by her own composure. “Send whatever you’ve got, mate.”

“Fucking shit,” he said, and pandemonium erupted on the channel as crews began to call up with their locations and availability.

She listened for a few seconds, reassured by how close some of the vehicles were, but let the radio drop when she heard Rosie cry out in pain.

“Rosie?” It was difficult to see clearly; the smoke was distorting the finer details, like a cobweb caught on her retina. She inched across to the lighter part of the room, her hands outstretched for obstacles.

“It’s nothing, stay put,” Rosie said, but she didn’t resume her hammering. Instead, Jem heard the cylinder drop to the floor and a whispered “damn it.”

She found the cylinder first, stubbing her toe on the metal and staring in horror at the blood coating its length. “What the hell have you done?” she said, yanking Rosie’s shirt to pull her around.

“Nothing.” Rosie stooped for the cylinder, but her fingers were bloody and she couldn’t grip it. “I cut my arm on the glass. Wrap it with something, Jem. Quickly, come on!”

“Put some pressure on it and keep it elevated,” Jem said, using her scissors to hack a strip from the closest curtain. Rosie’s “cut” was a deep laceration extending from her wrist to mid-forearm, and it was bleeding heavily. Jem bound the cloth around the gash, pulling it tight and knotting the ends. “Here, I can—” She went to pick up the cylinder, but Rosie took it from her.

“Fetch the girls. I just need to knock a couple more pieces out,” she told Jem. Then, softer, “Go on. I’m fine.”