I first saw him at a market up on the border with Bolivia. It was a sprawling affair that ran alongside the main road across the frontier. Most of its wares were laid out on tarpaulins in the desert dunes. This was at above twelve thousand feet in the Andes, and I immediately noticed he was finding it almost as hard to breathe as I was.

Even so, he was remonstrating passionately with one of the indigenous women selling her few goods. I was attracted by the odd couple they made: he was well over six feet tall, with long, straight blond hair down to his shoulders, and he was dressed from head to toe in black leather. She was squat, dark, her hair as black as his leather jacket, snaking in a thick plait down her back, and she wore the battered brown bowler hat typical of the local women.

At first, I couldn’t comprehend what the argument was about. Then I noticed that the blond stranger kept pointing to something on the woman’s blanket. In the middle of it sat three small, sad-looking armadillos, tied together by their legs, watched over by a grubby, barefoot boy with a torn red jersey and ragged jeans.

I realised that the leather-clad giant was shouting in a garbled mix of American English and broken Spanish.

‘Can I help?’ I said. ‘I speak Spanish.’

‘Can’t you see what this damn Indian is doing?’ he muttered at me. ‘She’s selling these poor armadillos for pets.’

I didn’t have the heart to tell him that in fact they weren’t being sold as pets, but that in this part of the Andes they were a great delicacy – and when they had been eaten, their armour-plated shells usually came in handy to make the body of a small guitar.

‘They can’t sell them like that,’ protested the blond giant. ‘They’re wild critters, they gotta be allowed to roam.’

‘OK, I told him, so what do you want to do?’

‘Tell her I’ll buy the lot,’ he said. ‘How much d’you think she wants?’

It took quite a while to convince the market woman that my new-found friend was serious, but after some complicated three-way haggling we succeeded in buying the armadillos for thirty US dollars. The grateful local woman quickly stuffed the notes inside her voluminous woolly jumper. The American, whose name I by now knew was Greg, was equally jubilant.

‘Right, now let’s set these babies free!’ With that he strode off behind the dunes, the three armadillos squirming and writhing under his arm. I didn’t even get the chance to warn him those critters had incredibly sharp teeth.

I went off in the opposite direction with my Argentinian companion. We walked even deeper into the hills to look for petroglyphs, paintings on the rocks. Centuries ago, this northern tip of Argentina had been part of the Inca empire centred in Peru, but which had conquered all the region. The valleys here still bore traces of the adobe fortresses they had built, and I already had a collection of pottery shards I liked to think came from the days before the Spanish conquest.

But I hadn’t seen anything like the vivid paintings we soon discovered on several huge boulders in what once must have been a mountain stream. The rocks were a glowing pink sandstone, and all over them were hunting scenes, pictures of men on horses - a novelty that the Spaniards brought with them- and yes, men with lances chasing what looked like armadillos!

By the time we got back to the main road, the market had dispersed. To my astonishment however, Greg was still there. In fact, he was sitting disconsolately beside the road, looking like some huge abandoned leather armchair.

‘Those sons of bitches robbed me,’ he said. ‘They took my wallet, my passport, my cameras, and those damned armadillos.’

I couldn’t really leave him there like that. So we loaded him up in our car, and took him into town, to the local border police post. This was a dusty whitewashed adobe building, marked off from the rest of the dirt road by a smart chain-link fence. A flagpole stood in the middle of the yard, with the blue-and-white Argentine flag hanging limply in the cold, thin mountain air.

This was in the weeks before the Argentine military took power in a coup that they euphemistically called a ‘process of national re-organization’- a re-organization that was to cost the lives of thousands of young Argentines. But Greg needed help, and I reckoned the local police captain owed me a favour: a few days earlier he had almost shot me by mistake when he was pursuing a would-be robber through the streets of the town.

There was no doubt though that he was suspicious of this six-foot three gringo and his English companion. His suspicions grew as I translated Greg’s story about the purchase of the armadillos and his claim that the same people who’d sold him the animals had robbed him. The captain had great difficulty understanding why Greg should want to buy these creatures anyway - doesn’t he know they’re riddled with fleas and TB, he snorted?

But it was when Greg, with me acting as interpreter, went on to describe what he was planning to do in Argentina that the captain’s eyes really shot up to the ceiling. Greg, I explained, was hitch-hiking about fifteen hundred miles south to the Valdes peninsula, where he wanted to see and photograph the whales that congregate off the Argentine coast in great numbers at that time of year.

‘He’s travelling all through our country, without money or documents, to see some whales?’ said the captain incredulously. Yes, I repeated, he’s a naturalist, that’s what interests him most in life’.

Things went steadily downhill from there. Greg had no money or obvious means if support. He could not say who he would be staying with in Buenos Aires, or on the Valdes peninsula. He could not say what his profession was, beyond being a member of the Audubon Society of America - something I tried hard to explain to the increasingly irate police captain.

Eventually, he had heard enough. He stood up, put on his cap with the blue-and-white bull’s eye insignia on the front, and ordered one of the guards to take the prisoner to the town’s one cell out the back.

Before he was led out, Greg managed to slip me a scrap of paper, which I crumpled in my hand.

I was out of town the next day, and it wasn’t until the morning after that I remembered Greg, and thought I should see what had happened to him. I arrived at the police post just as he was being hauled onto the back of a pick-up truck, with an escort of four bleary-eyed soldiers. I asked the police captain where they were taking him. He snapped: ‘he’s being transported to the provincial capital for questioning.’

I went over to Greg: ‘Keep well away from me,’ he said. ‘You’ve got me into more than enough trouble already’.

That was the last I saw of the giant American. A few weeks later, the much-anticipated coup took place, and I had worries of my own. It was only then that I came across the crumpled piece of paper he had written, still stuffed deep in my pocket.

‘Tell US consul Greg Benkowski of 2624b Cortez Street, Chicago Illinois, is held by Argentine authorities. I am innocent!’

By now, I was down in the capital, Buenos Aires, and thought I should try to find out what had happened to him.

They were reticent about speaking over the telephone to me - no phone was safe in those days. When I arrived at the US consulate, I was shown into a room with bare walls and a plain desk in the centre. One of those hatchet-faced lean young Americans in a tan suit, his mouth a line like a crack in a teacup, glanced at me in distaste.

‘It took us a month to persuade the Argentinian authorities that Mr. Benkowksi was an innocent man. They claimed he had been arrested near the Bolivian frontier after being seen in the company of another alien whom they suspected of investigating hidden trails across the border, and of taking part in an armed robbery in a frontier town.’

I left without another word.

A few months later, I learned the Argentinian expression ‘la mufa’- someone who brings bad luck to whoever they meet.

The Power of Prose