The last Friday afternoon in January found Robin sitting alone at the partners' desk in the agency's small office in Denmark Street, killing time before setting out to view a flat in Acton by reviewing the Groomer file.  There was a lot of noise in the street outside: comprehensive building work continued to cause disruption around Charing Cross Road, and all journeys to and from the office meant walking over planks, past pneumatic drills and the catcalls of builders.  In consequence of the racket outside, the first intimation Robin had that a prospective client had just walked in off the street wasn't the sound of the glass outer door opening, but the phone on the desk ringing.

On answering, she heard Pat's baritone.

'Message from Mr Strike.  Would you be free to visit Gateshead this Saturday?'

This was code.  Since last year's successful resolution of a cold case, which had earned the agency another flurry of flattering press coverage, two would-be clients of pronounced eccentricity had walked in off the street.  The first, a clearly mentally ill woman, had begged Barclay, the only detective present at the time, to help her prove the government was watching her through the air vent of her flat in Gateshead.  The second, a heavily tattooed man who seemed slightly manic, had become threatening to Pat when she'd told him there were no detectives available to take down the details of his neighbour who, he was convinced, was part of an ISIS cell.  Fortunately, Strike had walked in just as the man had picked up Pat's stapler, with the apparent aim of throwing it at her.  Since then, Strike had insisted that Pat keep the outside door locked when she was alone in the office, and they'd all agreed on a code which meant, in essence, 'I've got a nutter here.'

'Threatening?' said Robin quietly, flicking the Groomer file closed.

'Oh, no,' said Pat calmly.

'Mentally ill?'

'Maybe a bit.'

'Male?'

'No.'

'Have you asked her to leave?'

'Yes.'

'Does she want to talk to Strike?'

'Not necessarily.'

'All right, Pat, I'll have a word with her.  Corning out now.'

Robin hung up the phone, put the Groomer file back in the drawer and headed for the outer office.

A young woman with untidy brown shoulder-length hair was sitting on the sofa opposite Pat's desk.  Robin was immediately struck by several oddities in the woman's appearance.  The overall impression she gave was of scruffiness, even grubbiness: she was wearing old ankle boots that needed re-heeling, slapdash eyeliner which looked as though it might have been applied the day before and a shirt so deeply creased it could have been slept in.  However, unless it was a fake, the Yves Saint Laurent handbag sitting on the sofa beside her would have cost over a thousand pounds and her long black wool coat looked brand new and of high quality.  When she saw Robin, the woman caught her breath in a little gasp, and before Robin could say anything, said,

'Please don't chuck me out.  Please.  I really, really need to talk to you.  Please.'

Robin hesitated, then said,

'OK, come through.  Pat, could you tell Strike I'm fine to go to Gateshead?'

'Hmm,' said Pat. 'I'd have refused, personally.'

Robin stood back to let the young woman pass into the inner office, then mouthed at Pat 'twenty minutes'.