The London-to-Paris flight was unusually empty that day; entire rows of seats across the aisle as well as those behind and in front were vacant. In fact, he virtually had this entire section of the plane to himself. A luxury he’d never encountered before on a commercial flight, but one that suited him fine, allowing him to spread out a little. His old brown leather jacket and military olive-green canvas knapsack occupied the seat next to him, along with the crumpled newspaper he’d been idly leafing through earlier before losing interest. Ben didn’t really care much for following world affairs. He was relaxed into the steady thrum of the plane, still watching the sky drift by and thinking about nothing much in particular when a fellow passenger who was strolling down the aisle from the rear of the plane stopped by Ben’s row, gestured at the unoccupied seat next to him and asked courteously, ‘Please, may I?’

Ben studied him for a moment. He had an excellent memory for faces, but he couldn’t remember having ever seen this man before. The stranger appeared to be in his mid-sixties, though it was hard to tell. He wasn’t tall, wasn’t short, wasn’t fat, wasn’t thin. His grey hair was receding from a high forehead, but was otherwise thick and somewhat unkempt. Sticking-out ears and a large, thread-veined nose with a prominent wart to one side. He wore glasses with a heavy black frame and thick lenses that magnified his eyes like a lemur’s. His suit was dark and his shoes were shiny. Generally respectable-looking and unthreatening in his manner. He seemed to have some particular reason for wanting to talk, though Ben had no idea what it could be.

Experience had taught Ben to be a careful person, sometimes to the point of being cagey and suspicious. But his natural tendency, especially at a moment like this when he was at ease, relatively carefree and fresh from three very pleasant days spent with someone he was extremely fond of, was to be open and friendly. Maybe the fellow had stopped to ask if he could borrow the newspaper. Maybe his watch had stopped and he wanted to know the right time. Maybe all kinds of things.

Ben hesitated a moment longer, then cleared his stuff from the seat, dumped it on the floor at his feet and replied, ‘Be my guest.’

The stranger plucked at his trouser legs the way dapper Englishmen do before sitting down, then settled in the empty seat and peered curiously at Ben through the thick glasses.

‘Enjoying your trip, Mr Hope?’ He spoke softly, but there was no misunderstanding his words.