‘I know where you’re coming from, Oliver. We tend to avoid “totemic” words like “no” and “yes” because they are in fact more open to interpretation and inaccuracy than you might imagine. If I say “no” or “yes” I am confirming or denying the content of your question, and your question is open to interpretation. Indeed, I don’t know exactly what you might mean by your question, what you might mean by a charged and flexible word like “dangerous”, so a crude answer like “yes” or “no” risks all kinds of semantic pitfalls. However, an answer such as “Londoners have no reason to be alarmed” is precise and useful.’

‘But it doesn’t answer the question. It doesn’t say if the smoke is harmful.’

‘It does more than that. It makes the event less harmful. No one should go out there and stick their head in the smoke. Police and fire service advice is to stay away. We’re clear about that. But do you know what could cause more harm? Much more harm? Worry. Worry can impact your health in a dozen ways. Worry can shorten your life. Worrying about this event is much more likely to cause us harm than the event itself. By reducing worry, we are directly reducing the harm associated with the event. What if someone is concerned by the air quality, so they stay at home and miss a day at work? That’s unnecessary economic damage, unnecessary concern, unnecessary harm. This is precisely what I meant by our role in managing perceptions of the event: we are not concerned with the cloud of smoke as much as we are with the cloud of psychological consequences the event has created. The emergency services can deal with the combustion incident, while a public relations department can address the action of the event on the minds of the public. We can change the nature of the event for the better. We can do good that way. Our intervention here is essentially therapeutic.’

The atmosphere in the cabin had become stifling. How did they stand it? The reek of smoke was everywhere. The back of my mouth tasted like a petrol station forecourt and a space in my head had been surrounded by hoardings promising that a tremendous migraine was coming soon. As we left, Lily gave us both a tote bag containing a press pack, a couple of police and fire service leaflets, a squeezy fire engine with tips for preventing house fires written on its side, and a pen and USB drive bearing the Metropolitan Police emblem. She thanked us for stopping by, and for our interest in the event, and took my business card, promising to sign me up for an email.

Pierce held the cabin door for me.

‘Patricia Highsmith,’ the policewoman at the desk said.

‘Excuse me?’ I said.