Henderson grabbed his suitcase as Marc pulled across two heavy bolts and opened the back door. Beyond the stairwell the ground floor comprised a single large room. They moved amongst desks and cabinets, separated from the waiting area at the opposite end by an ebony countertop and spiralled gold rails.

Marc was fascinated by the tools of bureaucracy: typewriters, rubber stamps, carbon papers and hole punches.

‘So they keep blank passports here?’ Marc asked, as he stared at the banks of wooden drawers along one wall.

‘If they haven’t run out,’ Henderson said, as he slammed his heavy case on a desktop, tilting a stack of envelopes on to the parquet floor. ‘But we can’t make a passport without a photograph.’

Henderson pulled a leather wallet out of his case. The miniature photographic kit comprised a matchbox-sized pinhole camera, tiny vials of photographic chemicals and sheets of photographic paper large enough to produce the kind of pictures used in identity documents.

‘Go stand under the wall clock,’ Henderson said, as he worked with the tiny camera, inserting a small rectangle of photographic paper.

Henderson looked up and saw a peculiar mix of apprehension and emotion on Marc’s face.

‘Nobody ever took my photograph before,’ he admitted.

Henderson looked surprised. ‘Not at the school or the orphanage?’

Marc shook his head.

‘We’ve got very little light,’ Henderson explained, as he propped the camera on a stack of ledgers. ‘So I need you to stay absolutely still and keep your eyes open.’

Marc stood rigid for twenty seconds, then rushed forwards on Henderson’s signal.

‘When can I see it?’ he asked, as he blinked his stinging eyes repeatedly.

‘I have a developing kit,’ Henderson explained. ‘There must be a kitchen somewhere. I need you to find me three saucers and some warm water.’

As Marc raced upstairs to find the kitchen, Henderson began looking around the offices for blank passports. He discovered an entire drawer full of them, along with a wooden cigar box containing all the necessary stamps and, most helpfully, a crumpled blue manual detailing the correct procedure for dealing with a consular passport application.

One of the telephones rang, but Henderson ignored it and began shaking his photographic chemicals, ready for when Marc came back with the water.

A second phone thrummed as Marc came downstairs with three saucers and a tobacco tin filled with hot tap water. Henderson found the ringing irritating, but with France in chaos it didn’t surprise him that the consular phones would ring through the night.

‘I need absolute darkness to develop the photograph,’ Henderson explained, as he spread out the three saucers and dipped a fragile glass thermometer in the hot water. ‘Get the lights.’