The lyric perfection of the works of Alfred Tennyson, one of the greatest Victorian poets, and the apparent ease with which he wrote them, long obscured the disparity between the unruffled surface of many of his poems and his deeply disturbed life.

Somersby Rectory, where Tennyson was born, was made miserable by drunkenness, drug addiction, threats of violence, melodramatic disinheritances, and above all by the fear of madness. He found an anodyne for his unhappiness in the composition of poetry, and was so successful in this refuge from the bewildering complexities of his life that he eventually became Poet Laureate and the most famous of living writers.

Until he was forty years old the belief that he suffered from inherited epilepsy kept Tennyson unsettled, neurotic about money, immature in his relations with women, and apprehensive of marriage. It was a belief that gave shape to some of his finest poetry.

At the end of his life Tennyson''s wife and son constructed a public façade for him of irreproachable normality and respectability. Robert Bernard Martin was the first biographer to go behind the mask of the troubled poet to investigate his black-tempered morbidity, and neurotic secrecy about his private life. More importantly, it often reveals the sources of the successes and failures of the foremost Victorian poet.

From many thousands of letters by Tennyson, his family, and his friends, as well as much other unpublished material, Robert Bernard Martin has distilled a sensitive and sympathetic portrait of Tennyson, both as his contemporaries saw him and as he was in private.

''Tennyson: The Unquiet Heart will stand as one of the great literary biographies of this century.'' A. N. Wilson, The Spectator