I sometimes lie awake thinking of ways to kill him. Actually kill him. I wonder if I can drill a hole in my ceiling, feed a rubber hose through his floor and fill his place with carbon monoxide. I wonder if I can set fire to the building at night and burn him to a crisp. I wonder if I can loosen a step, or set up a tripwire, so that he goes tumbling down the stairs and cracks his skull open. I wonder if I can attach something to his car so that it blows up when he turns on the ignition – that sounds ridiculous but I know how it’s done. And it goes without saying that if you could kill someone by pressing a button – just pressing a button and leaving no forensic evidence whatsoever – I would’ve finished him off a hundred times, a thousand times, by now.’

Cat could hear her own voice in her ears – with a sort of disembodied horror – but she couldn’t stop.

‘And even when I’m not thinking of ways to kill him, I’m dreaming of ways he might be killed. Maybe that light plane I hear buzzing overhead will drop out of the sky and crash into the top floor – just the top floor. Maybe the landing gear will fall off that jetliner. Maybe that storm will send a branch spearing through his window. Maybe that shooting star is a meteor heading straight for his head. You can’t imagine how many ways I’ve fantasised about this guy getting crushed, sliced open, ripped apart. And yeah, that’s shocking, and yeah, I wake up in the morning thinking, “My God, what’s the matter with me?” But that’s what happens when you’re at your wits’ end. When you’re tired. When you’re not thinking straight. When your peace of mind is suffering, when your health is suffering, when the only answer seems to be doing something that was previously unthinkable.’