Tucked behind the fence were two conjoined white portable huts, like the office on a construction site. Under the emblem of the Met were the words ‘Rapid Response Incident Media Assistance’. A male police officer minded the door, barely acknowledging us as we climbed the unsteady steps to enter. Inside, a female police officer sat behind a desk in a smart dress uniform, her shiny buttons the brightest objects in a thoroughly bland environment of fibreboard, acoustic panels and cheap carpet. She cocked her head at us.

‘Good afternoon,’ Pierce said.

‘Good afternoon,’ the police officer said. ‘Media?’ she asked, doubtful.

‘Yes,’ I said.

‘Do you have ID?’

Fortunately, I did. I pulled out my wallet and produced a business card and my NUJ card. Pierce followed my actions, hesitating a little before showing a small, teal plastic card of his own.

My NUJ credentials were accepted with a minimal nod. Pierce’s card was taken from him for closer examination.

‘Society of Authors?’ she said.

Pierce smiled. ‘I’m an author.’

‘This is expired.’

‘I’m an expired author.’

‘Oliver Pierce,’ she said, weighing the name for falsity.

‘That’s me,’ Pierce said, cheerful. I had spent more than an hour praying for him to do something memorable or outrageous, to unleash the caper, but now he looked ready to embark on mischief I found myself praying that he behaved himself. In and out, get this over with as quickly as possible, keep moving.

‘I wrote a non-fiction book about crime,’ Pierce continued. Is it an offence to lie to a police officer? Even in casual conversation? Although there was nothing very casual about this conversation. The officer was sandblasting Pierce with her gaze, as if expecting the paunchy author exterior to slough away, revealing a jihadist beneath. ‘About street crime. And a crime novel, for that matter. Kind of. It isn’t shelved in Crime. Perhaps you’ve read them?’

‘No,’ the officer said, the words bleached of tone. That might have been lucky. The Met had not approved of Night Traffic. And I thought, Forget the literary scandal, was there a possibility that Pierce might find himself in criminal trouble over his fraud? Had he considered that?

‘Pity,’ Pierce said. The police officer returned Pierce’s card, and Pierce returned it to his wallet. She said nothing, and little could be read from her face, other than homeopathic quantities of boredom and disapproval. There was no word or nod or wave to endorse or authorise our passage, nothing even slightly affirmative. We were simply no longer stopped from proceeding.

While we were having our cards read, someone had emerged from the screened-off area to meet us: a sparkling young woman in taut business attire. At a glance, I knew her – I knew her by type. I dealt with her kin every day. She worked in public relations.