DESPITE a professional life that extended over half a century, Richard Hughes (1900-76) produced only four full-length novels. Two of these, A High Wind in Jamaica and The Fox in the Attic, separated by a gap of 30 years, were considerable best-sellers. In between came a piecemeal living on the dreariest kind of hack work, even extending to unfilmed scripts for Ealing studios. The chief paradox of Hughes's career rises inexorably to dominate Richard Perceval Graves's painstaking biography: how a man who exulted in the 'life sentence' of the writer's calling could find the act of writing such perpetual torment.

The streak of restlessness which was to interrupt his later career was, as Graves shows, ingrained early on. As well as a glut of plays, poems and stories, Hughes's early twenties took in a surfeit of foreign adventures: a holiday down the Danube spent interfering in Balkan politics on the side of Croatian nationalism; hair-raising travels in the Near East and North America; house-buying in Tangier. By the end of the Twenties his metamorphosis from patriotic public schoolboy to literary man of action was complete: the physical extremes to which the cast of A High Wind in Jamaica (1929) are exposed have a definite grounding in his own life.

But it would be a mistake to mark Hughes down as a kind of home-grown Jack London. One of the sharpest characteristics thrown up by Hughes is an adaptability to circumstance that had a habit of propelling its subject into highly conventional patterns of life and thought. Even in his undergraduate days at Oxford, when a blasphemous poem had him threatened with expulsion, Hughes immediately rescued his career by agreeing to apologise. Later, after a successful war as an Admiralty civil servant, he was happy to follow the Foreign Office line on East European literary gatherings, or rebuke Graham Greene's opposition to Vietnam. The children of his marriage to a quintessentially genteel Englishwoman went to public schools.

The picture of a fiery Cambrian savant is similarly hard to square with increasingly frenzied attempts to earn a living. Endlessly seduced by new schemes, he took until 1961 to produce The Fox in the Attic, and Graves's account of his writing life in the Fifties is often a list of aborted projects. Increasingly absorbed in The Human Predicament, an ambitiously conceived work on the pre-history of the Second World War of which Fox was the first volume, he managed only one further novel - The Wooden Shepherdess in 1973 - and the scheme died with him.

Graves's biography, written in the conviction that both Hughes and his work are undervalued, is more a recitation than a piece of analysis. Occasionally pedestrian in style, he is reluctant to engage with what on the surface seem to be crucial passages in Hughes's life or temperament. Hughes's sexuality - his cancelled first engagement and the interest in small girls - is one obvious absence, but this lack of inquisitiveness extends into other areas. The publication of his first two (admittedly minor) books in 1926 goes by in a paragraph; some potentially revealing dinner dates with Evelyn Waugh disappear in a sentence.

More important, perhaps, is the relative silence on one of Hughes's most settled beliefs: the futility of a writer taking a political stance. This lay at the heart of his quarrel with Greene and his disagreements with Koestler. And quietism, one imagines, is also a cause of his comparative neglect. It is not simply that Hughes wrote a kind of highly intelligent action novel that has gone out of favour, but that in the age of Orwell, Auden and Co, his detachment makes him seem a diminished figure. For all Graves's enthusiasm, one can't help feeling that his subject is probably beyond reclaim.