He seemed like a normal enough kind of chap at first...

The train to Salisbury was three carriages long. The carriages weren’t proper compartment carriages with corridors and sliding doors and impeccably-coiffured fur-clad ladies gazing wistfully at the passing scenery, their nylon-clad legs demurely crossed.

Each carriage was separate, with no end doors and therefore no access to the adjacent one.

I was sitting at the end of the middle carriage, by the window, with my back to the end wall.

I too was gazing wistfully at the passing scenery with my nylon-clad legs demurely crossed.

Sitting diagonally opposite me was a man. Sitting at the other end of the seat I was on was another man. He was smoking a cigarette. So was I. These were the days when you could smoke on a train. The days when you weren't branded a social leper for doing so, and the days before I met Mrs Le Pew and she told me to stop it.

There was an attractive young lady sitting facing us, on the next row of seats. Had she been sitting opposite herself, she would have had her back directly behind the man sitting diagonally opposite me.

The man with the suitcase.

It was a diesel train.

It would have been nice to say that it was a steam train, and that as it thundered through the Wiltshire countryside, I opened the window and turned my face into the onrushing breeze, peering through streaming eyes as the muscular locomotive leant purposefully into the wind and pummelled toward the horizon, shovelling rolling billows of smoke over its shoulder, pistons hammering and connecting rods a blur of polished steel.

But it wasn’t a steam train.

It growled and swayed and clickety-clacked across the fields, stopping at Bulgehampton, Hyssington Mal-de-Mer and Cringeworthy-cum-Frequently in a squeal of brakes and an inelegant lurch, each which brought a small sigh of irritation from the girl opposite as she lost her place on the page of the book she was reading.

I had given up trying to catch her eye. I was trying to catch her eye just to see if I could. She was probably about the same age as me, and because she had auburn hair, she was an object of not inconsiderable lust.

Occasionally the man sitting diagonally opposite me got to his feet and took down the suitcase which he had stowed on the empty rack which ran from above my head to a point above the head of the man who was smoking – or rather had been smoking – a cigarette.

I was still smoking mine because it was a roll-up, and because it had gone out several times. I couldn’t afford proper cigarettes in 1975.

The suitcase was about the size of an attaché case, but rather deeper, and each time he took it down from the rack he set it on his knees, opened it four or five inches, rearranged something inside, closed it and replaced it on the rack.

He never took anything out, and he never opened it enough to allow anyone else to see inside it.

The next stop was at a station comprising a wooden platform the approximate size of a wallpapering table in the middle of a large field. A track meandered through the field to get to it, and the field contained several rather comely Friesian heifers. Two of them were licking a bicycle that was leaning nervously against the side of the wooden steps which climbed lazily to the platform.

No one got off, and no one got on. In fact, there was nobody in sight for miles around. This didn’t prevent the train from waiting for several minutes, gently chuntering to itself.

The man got the suitcase down again, but this time I noticed that both the redheaded girl and the man who had been smoking a cigarette but now wasn’t were both watching him. She watched from over her book; he from the corner of his eye, feigning disinterest by not turning his head. The man replaced the suitcase, sat down, adjusted his tie, and took what appeared to be a Mint Imperial from his jacket pocket.

He put it in his mouth.

The following station was a proper station, with a waiting room, conveniences and a heavy metal-wheeled luggage barrow on the platform.

On the barrow was large wooden box with some writing on it. The writing had clearly been done with a stencil, a brush and some black paint.

The train drew to a halt with a lurch and the suitcase man stood up. This time he didn’t get his suitcase down. He walked to the door, and, after a little difficulty, lowered the window, reached out, turned the door handle and stepped out onto the platform. He closed the door behind him, and without glancing back strode off in the direction of the waiting room.

His suitcase remained on the rack.

A little while later, probably about four minutes or so, there was a shrill peep from the stationmaster’s whistle. The train groaned and began to move. Within a few seconds it had accelerated to a trot, then a canter, and finally, as it passed the end of the platform, to a speed which would have required the lung-bursting sprint of a hundred-metre runner in peak condition to keep pace.

The seat previously occupied by suitcase man was conspicuously empty.

Although none of us said anything, we were each acutely aware of what the others were thinking.

Had he missed the train? And if so, had he deliberately missed the train?

Was there a bomb in the suitcase? None of us moved, but we each knew that the others were listening intently to the brown case on the rack; listening for a tick; straining to catch the almost imperceptible sound of tiny electrical contacts closing.

Perhaps he hadn’t missed the train at all, and was hanging grimly to the door handle, being buffeted by the slipstream, and having his shoes ripped from his bloody feet by the repeated pounding as they hit the sleepers.

Would there be a scarlet trail spattered in the trackside ballast that would lead police to an inert body by the points, its hand frozen in death, reaching despairingly and agonisingly for the fast-dwindling and long-disappeared train?

Maybe the poor chap was sitting on the platform at Snodsbury Maltravers with his head in his hands, sobbing gently to himself as a fortune in uncut emeralds disappeared towards Salisbury’s elegant spire.

Perhaps he’d been to relieve himself, and found his visit requiring the sit-down he was hoping not to make until he was back at home. Unexpectedly inconvenienced, he simply could not make the departing train in time, and was now obliged to wait five hours for the next one.

Perhaps he was a spy, and having left the blueprints on the train, was even now removing the small cyanide capsule from where it had been carefully stitched into his lapel.

Though we didn’t speak, we knew we were all thinking the same thing. We also knew we were all wondering whether or not we should open the case. And just as we were all wondering who would be the first to say something, the train slowed, and eased into Whimperingley Magna with another lurch.

Before any of us could gather our thoughts sufficiently to act, the door opened and suitcase man got in.

He glanced briefly at his case, hitched his trousers, and sat down.

He had to have been running alongside the train at upwards of thirty miles an hour, yet he hadn’t even broken sweat! There was absolutely noting to suggest that he had run pell-mell for more than four miles. None whatsoever.

It was extraordinary. Perhaps he had indeed clung spider-like to the outside of the carriage, yet he looked as neat and tidy as he had when the journey began.

All these questions remained unanswered as we disembarked in Salisbury.

The three of us who witnessed these remarkable events never spoke about it. We barely exchanged glances. I shouldered my rucksack and set off to my girlfriend’s parents’ house in The Close. The cigarette-smoking man hailed a taxi, and the pretty auburn-haired girl was met - and kissed - by her very large boyfriend.

Suitcase man?

He melted away into the crowd.