The Quiet Man: Guinness on stage: Sir Alec Guinness is 80 next month. David Thomson and Irving Wardle look back on a 60-year career that spans stage, film and television

OF ALL the leading actors who emerged from Gielgud's West End companies in the 1930s, Alec Guinness was the least obviously cut out for the heroic stage. Among his Olympian peers, whose voices rang unmistakeably through any depth of character make-up, Guinness achieved stardom by the opposite process of disappearing into whatever he was playing.

A slight figure, his most conspicuous features were the prominent ears which Gielgud said gave him the appearance of a 'starved charity child'. If there is any personal subtext underlying his career it is the fable of the downtrodden nonentity who proves himself a person to be reckoned with.

Theatrically, he first made his mark as a chameleon artist who specialised in creating something out of nothing. More substantial parts came his way when he moved to the Old Vic (under Tyrone Guthrie) in 1936; but none of them won more acclaim than his appearances as Romeo's Apothecary, and a string of Shakespearian attendant lords whom he rescued from invisibility. He disdained eye-catching make-up and dismissed the post-war Old Vic as a 'hotbed of false noses'. Transformation for Guinness was 'all done from inside'. His work resists external description; it can only be conveyed by observing his thought processes.

More dazzling off-centre performances (the Fool to Olivier's Lear, and Abel Drugger in The Alchemist) followed when he returned to the Vic after the war. But by this time Guinness had emerged as a stage writer, with his adaptations of Great Expectations (1939) and The Brothers Karamazov (1946). The second of these (in which he played Mitya) also foreshadowed the line of near-saints and lost souls with which he found his true territory. Guinness as Hamlet or Macbeth was inconclusive: as Sartre's Garcin in Huis Clos (1946) and the Uninvited Guest in Eliot's The Cocktail Party (1950) he was incomparable. It is one of the secrets of Guinness's talent that this coincided with his renewal as a mischievous comedian - in such startlingly carnal roles as the transvestite crook in Simon Gray's Wise Child (1967) and the sexually backsliding MP in Alan Bennett's Habeas Corpus (1973).

His superbly written memoir, Blessings in Disguise, leaves you wondering why he has published nothing else. In it he repays his debts to the colleagues who helped to shape his life. It tells you a lot about them. Of Guinness himself, it tells you virtually nothing. IW