You should never, admonishes Geoffrey Elliott, "try to dig up a long-lost parent''. Spectacularly ignoring this last item in his own drawn-up list of "basic rules in life'', the author of `I Spy', has come up with a fascinating biography of a swashbuckling, if shadowy protagonist, whose exploits were obviously too hard to resist.

Of course, not many of us can claim a father who was employed as a British secret agent, parachuted into the mountainous terrain of Yugoslavia at the height of World War II to spy on guerrilla activity, and who survived interrogation by the Gestapo before being tossed, as a prisoner-of-war, into a turretted castle straight out of Grimms' Fairy Tales. After the war, in spite of his "grey-flannelled'' cover as Unilever's general manager, he was also interrogated, in circumstances that, even now, remain largely unexplained, by the Hungarian secret police during the early days of the Communist takeover.

His prolonged incursion into international intrigue and skullduggery came to an abrupt end when he was finally booted out of that country in 1949. In spite of a second marriage (and second family) a spell in pre-independent Jamaica did nothing to enhance his career which, says Mr. Elliott, tapered right off just as the Cold War gained momentum.

"I never really knew my father,'' he explains. "I was born in 1939, just as war was breaking out and only met him, as a child, on about three occasions.

So I have been able to detach myself from him.'' Nevertheless, intrigued by the mystery of his father's life and origins, and armed with only a few bits of paper and a couple of photographs, the author spent countless hours and long journeys tracking down the answers. Sometimes through meticulous research, sometimes through luck, he has scored several hits. Perhaps it is his training in the unemotional world of banking that has enabled him to assess and sift so coolly and even-handedly through the reminiscences of his father's former friends, colleagues and possible enemies.

The result is a volume that reads like a thriller, laced with poignant undertones but revealing, also, on almost every page, a wry sense of humour.

"It was just as well that I did most of the work on this book soon after I retired,'' concedes the former banker who has since busied himself in Bermuda affairs. With his wife Fay, Mr. Elliott has been a generous benefactor to the arts and serves as chairman of the executive committee of the National Gallery, as deputy chairman of the Land Development Company, and is also involved in Tourism's `Monitor' project.

Perhaps it was the author's own spell, as a young officer in the British Intelligence Corps, that fed an increasing, if apprehensive curiosity about his father's career. He was already painfully aware, from his childhood on, that those brave, often rash war-time deeds were performed by a man who, in the parlance of the day, was a bit of a cad, leaving his wife and children, often without money, to cope with his long, unexplained absences as best they could.

Kavan Elliott became deeply embroiled in the internecine strife that seems, still, to loom large in the extremities of eastern Europe and the Balkans. His son -- who also, rather bravely, has faced head-on, some unpalatable truths about his father -- lays bare the facts surrounding the extraordinary career of this larger-than-life, pleasure-loving, high-spending, hard-drinking man who, in best Bond-fashion, also tended toward passionate, if short-lived liaisons with beautiful women.

Accustomed to an exciting world of deceit and double-dealing carried on in exotic locations, Elliott Sr. ended up in what for him must have been a dismally unlikely setting -- behind the counter of a sub-post office/cum village shop in Berkshire. Even this last enterprise ended in disaster for, when facing exposure from postal authorities for `borrowing' from the cash register, Elliott and his second wife staged a bogus hold-up. When this was rumbled, it was she who was charged and placed on probation. Clues on this curious episode were given to the author by none other than Auberon Waugh, writer son of another very difficult and famous parent, Evelyn Waugh.

While condemning the lies concocted by his father about his background, Mr.

Elliott believes it was the escapist world of the cinema that had probably bolstered his father's exaggerated sense of glamourous make-believe.

Acknowledging his brilliance at languages (a gift inherited by his son), Mr.

Elliott believes that his father's successful leap across the rigid class barriers of pre-war England was possibly his greatest achievement. "He came from a working-class family. It's not clear who his family was. I know that he left school at 14, so he did very well. He became a major in the army and was then recruited for Intelligence. That really was quite a feat -- especially back in those days.'' He had, predictably perhaps, even chosen a wife (Geoffrey's mother) from a somewhat exotic background, since her maternal grandfather, a Menshevik revolutionary, had been banished to Tsarist Siberia before settling in England. There, the family established what they named the `Balkan Sobranie' cigarette business: as Mr. Elliott notes in the book, although there was no love lost between the young suitor and his grandfather (he would step into the financial void left by the desertion of the secret agent), there was a fateful affinity between the two as "Elliott's lanky shadow fell across her path....Balkan Sobranie met Balkan Joe''.

A resident of Bermuda for the past ten years, (describing, in the book, his adopted home as "a micro-sized triumph of myth over reality'') Mr. Elliott admits that after retirement as managing director of Morgan Stanley in New York, he became more and more tempted by the idea of solving some of the puzzles surrounding his father's life -- and, by extension, his own. "It was a bit like finally clearing the attic,'' he explains. "I didn't have much to go on, to begin with. I knew my father had acquired a second family, but little beyond that. The first thing that I actually found out was that he had in fact, died. Then, I came across a brief reference to his war-time mission to what we may as well refer to as Yugoslavia.'' Encouraged, Mr. Elliott then began the extensive research that took him to the pre-war archives of Bulgaria, as well as the archival records of Germany and Yugoslavia: "So, gradually, I began to get a very good picture of what had happened and I became very interested in pursuing the Hungarian angle. I got a couple of snippets from the British Public Records Office and began to realise, from various conflicting reports, that something very strange had been going on there!'' That `Hungarian interlude', which at times reads like a Le Carre novel, involved the arrest of both Elliott Sr. and his beautiful mistress `Kati'; there was subsequent speculation that she had been a "honey-pot'' planted on the luckless agent by the communist overlords. After his expulsion from Hungary, Kavan Elliott never really regained the confidence of his British spy-masters. "I suppose the truth of what really happened lies somewhere in between the various accounts,'' says the author who refers to his father in suitably, and understandably unfilial fashion, simply as `Elliott' throughout.

Amazingly, Mr. Elliott managed to track down `Kati', and even retrieved some of her letters to his father, and has therefore been able to add her version to the cloak and dagger events surrounding that time. "So what the book is saying,'' Mr. Elliott adds enigmatically, "is that you, the reader, must decide what really happened.'' It is a story which, half a century later, still fascinates.

`I Spy: The Secret Life of a British Agent' by Geoffrey Elliott, is now on sale in Bermuda and is published by St. Ermin's Press.

WARTIME REUNION -- During a rare break at home in wartime England, British agent Kavan Elliott poses for a picture with his son Geoffrey.