Using that corner as a starting point, Rosie zigzagged across the floor, trying to cover as much of it as possible whilst keeping a close eye on where she was putting her feet. Several sections of the concrete had traps cut into it, covered only by rotting wooden doors and almost impossible to spot, even in daylight. Someone had splattered a couple with yellow paint, but a large hole in the centre of another implied Mickey Foss wasn’t the only one to have come a cropper in here. Kneeling by the gap, she directed her torch through it and leaned low, straining to pick out objects in the murk. Dank air hit her face, bringing with it a stagnant tang, and she could see floodwater several metres below, its ink-black surface rippling in the draught. She shivered, pushing away from the edge and then dusting off her knees as she stood. A quick check of her watch told her she had twenty-five minutes left before Jem might raise the alarm, but there was only the very back of the room still left for her to explore.

Following the rear wall brought her to a recess housing a flight of stairs. Happy to heed Jem’s warning about the upper levels, she was about to call it a day when a sudden smash of glass and a stifled laugh sounded clearly from the floor above.

“Shit.” She kicked the dusty bottom step, glaring at its fresh footprints. The prints were smaller than hers and overlapping, suggesting more than one person was up there.

The first step creaked but held as she put her foot on it. She set her jaw, resigned to her fate and somewhat comforted by the prospect of Jem being sent to her should she break her neck. Jem would no doubt be less than impressed, however, so she crept upward at a snail’s pace, avoiding any obvious weak spots in the wood and holding the handrail in the few places it was securely fixed. Still hidden in the alcove at the top of the flight, she mulled over her options. The last thing she wanted was to spook anyone and have to chase after the buggers, so she tiptoed to the door and pushed it open a crack. She could hear three distinct and distinctly young voices: two girls and one lad. The kids were close by and to her left, and judging by the smell that hit her, they were all stoned.

“Yeah, but it’s not unpossible is it?” the lad said. “They’ve got a horn.”

One of the girls laughed. “They’ve got antlers, y’thick twat, not horns, and they’d never shag a horse.”

“So where do they come from, then?” he asked, after a prolonged spell of inhalation that ended with a violent fit of coughing and another wave of dope smoke wafting over Rosie.