He gave a grunt of pain and tottered, his own blow going askew, the blade’s edge skittering along the bricks. Lucy rolled away along the wall, and almost by accident passed through the doorway into the next section of the building, where she saw the lowermost steps of the flight she’d remembered. She scampered up it, jabbering into her radio.

‘DC Clayburn to Foxtrot Alpha! Immediate assistance required … I’m in “A” Block, Reddington Hall, under attack. I’m uninjured, but haven’t yet found a secure position. Armed suspect very close behind me … urgent assistance, over!’

Grunting and panting, she heard her assailant commence the ascent.

She gasped as she reached the top of the stairs, and found the three corridors leading off in opposing directions, each one dark, dank and, though zebra-striped with moonlight from the broken-open doors along them, looking almost impossibly sinister.

One of these routes led to an exit. She remembered that much, as she lurched down the corridor on the left. This was the one she wanted, she was sure.

She blundered through patches of moonlight, stumbling over broken furniture and gutted mattresses, skidding in pools of slimy water.

And with heavy, lumbering footfalls, he came after her.

‘That’s it … don’t quit on me,’ she breathed.

She even slowed down, so that he was no more than fifteen yards behind, puffing and panting as he hobbled along but able to see her. Ahead, meanwhile, the corridor looked as if it came to a dead end, a blank wall of shadow – but this was deceptive. What was really here, concealed in blackness, was a wooden fire-exit door. Also concealed, just to the right of this, was the entrance to the last flat. Of all the squats they’d broken into nineteen months ago, this one had been the best defended, because when they’d entered, they’d found that it wasn’t just a shooting gallery for smackheads, but a drugs den, where the dealers stored their merchandise and weapons. The door itself had been lined with steel and fixed with brand-new bolts. The police raiding party had assailed it with sledgehammers and eventually a hydraulic ram, which had not just brought the door down, but the lintel too and all the surrounding bricks and masonry.

What remained now was exactly what Lucy remembered: a jagged, cavern-like entrance, only blackness and rubble lying beyond. All around the edges, loose bricks hung from rotted mortar. Lucy didn’t waste time choosing one. She grabbed the first she could, waggled it free and swung around with it, bringing it up and over her shoulder like a cricket ball, and as the Creep came at her, smashing it into his face, jarring her shoulder, but dragging a surprised and horrible squawk from out of him.