No. 23 has a secret. In this gloomy, bedsit-riddled South London wreck, lorded over by a lecherous landlord, a horrifying collection quietly waits to be discovered. Yet all six residents have something to hide. Collette is on the run from her ex-boss; Cher is an underage children's home escapee; lonely Thomas tries to make friends with his neighbours; while a gorgeous Iranian asylum seeker and a 'quiet man' nobody sees try to keep themselves hidden. And there for them all is Vesta, a woman who knows everything that goes on in the house - or thought she did. Then in the dead of night, a terrible accident pushes the six into an uneasy alliance. But one of them is a killer, expertly hiding their pastime, all the while closing in on their next victim...As a cloying heatwave suffocates the city, events build to an electrifying climax in this brilliantly constructed, tightly paced thriller.

Winner 2015 Macavity Award for best mystery novel.