AS CLEAR AS GLASS : Sir Alec Guinness.

Since his death in England last month at age eighty-six, I have been reviewing the films I could find of the great and elusive Alec Guinness, and lamenting the ones I could not find or had never seen.

I have never seen The Prisoner (1955), in which he plays a Roman Catholic cardinal imprisoned in an Iron Curtain nation during the cold war--a man imprisoned also by his own beliefs and doubts. Guinness played the part on stage and in film, and is said to have been even better in the stage version. It strikes me as a role he was born to play, and one that no one else could play with his insight and sympathy.

He's awfully good in his two other priest roles: as Monsignor Quixote, in a 1985 BBC production based on the Graham Greene novella of the same name, and as Father Brown in The Detective (1954), the one Chesterton adaption he did on film. (What a pity there were not more.) In both of those parts Guinness got to be a clown (an oafish, unself-conscious clown) and a man of depth. This was perfect for him. In so many of his straight parts the ironic inflection, or look, peeks out but cannot stay. And in the comedies there is an underlying sadness--like Buster Keaton's.

Certainly there was something priestly in Guinness: something at once intimate and detached; a bit sexless, in a fussy way; and, of course, there is that amazing quiet and stillness. (Is not master spy George Smiley priestly, and is not that both his blessing and his curse?) Laurence Olivier was all motion, even if it was only his face in camera. Guinness was stillness.

Also priestlike was Guinness's deflection of attention from himself. What one often hopes for in a priest is the ability to escape the ego--to listen. Guinness, in every part, appears to be listening and watching. And if you read his diaries and multivolume autobiography, specifically Blessings in Disguise (1986), you find out he was doing just that in private life. He was picking out his little bits of this or that characteristic to meditate on, absorb, and appropriate--a shuffle here, a dialect there, a mannerism too odd to be seen as stage business.

I'm sure I first saw him in The Bridge on the River Kwai (1957), when I was too young to "get" the movie or his character. Seeing it years later, I was astonished. And I was astonished also, after Guinness's death, to read the common journalistic verdict that the duty-bound prisoner of war Colonel Richardson was mad. Was he? Surely the point was that one couldn't finally say whether Richardson was impossibly noble or impossibly nuts.

And this is the point of Guinness's art. He never lets you see more than a few burning embers. He never takes you all the way below the surface. And he never cheapens the character.

It was often said that he disappeared into the character and was a man of masks. True enough, technically. But you always knew it was Guinness. That quiet centeredness was the core of every portrayal.

The tube gave me my first glimpse of how good Guinness could be. It was a BBC import of Shaw's play Caesar and Cleopatra, and Guinness was an incredible Caesar--tragic, detached, and self-aware. He played the part as a grown-up Hamlet, with touches of Gandhi, Adlai Stevenson, and a hit man. And there was not an ounce of the maudlin or sentimental.

Guinness and Olivier both played the blind English barrister in John Mortimer's A Voyage Round My Father (1971). Olivier played him (on film) as a mean old SOB who was lovable in spite of himself. Guinness played him (on stage) as a mean old SOB who was utterly unlovable, but who demanded love.

He said he was not an actor in the league of the really great ones. Of the finest English stage actors of his era--John Gielgud, Laurence Olivier, Ralph Richardson, and himself--Guinness seemed to rank Guinness a proper fourth. Certainly he was not as heroic as the others. And there is no doubt that he never bested the Bard as the others did. But there was something pure about his acting. It is acting without ego, if such a thing is possible. It is not all technique and masks, but a sort of clear glass. He goes right to the heart of the playwright's creation, cutting out the middle stop at the actor's star turn.

I would have loved to see Guinness playing Dean Swift, in a one-man show of the actor's own devising. Or as Dylan Thomas. Or in the Alan Bennett plays he did in London's West End in later years. Guinness actually loved the theater more than films, and he loved it for reasons that seem very Catholic: the rituals surrounding preparation and production, the corporate nature of theater work and friendships, the reliance upon text versus image. He was a sacred text man, to be sure, one who knew passages of Shakespeare, Jane Austen, and e.e. cummings by heart.

But his greatest successes were on film. And he was by far the best and most successful of his generation in the movies. It seems a sacrilege that Gielgud is best remembered for the Dudley Moore farce Arthur. And Olivier, except for his great Henry V and his very, very great Lear, made mostly dreadful movies, which he often made worse by the hammiest of ham acting.

Guinness was often, and probably justly, accused of underacting in the movies, but never of overacting. The cliche is that film is the director's sandbox, stage the actor's. Guinness made film an actor's medium, with sheer variety of roles and inventiveness (also the mark of his stage career), and, at the same time, the directness and truthfulness of his characterizations. He always improved the bad movies he was in. Star Wars (1977) would have been Buck Rogers without him. He couldn't save Lovesick (1982), but it is worth watching to see Guinness as Freud.

His faith was not important to his craft in any way that I can detect, except that it was important to him. He said that his conversion to Catholicism (along with the music of Haydn) kept him sane. He never quite explained that because, I gather, he thought he didn't need to. Guinness himself told the story of taking a break during the filming of The Detective one evening in France. He strolled down the street in his priest's cassock and a little boy he had never seen before sidled up to him and silently took his hand. They walked along in silence, and in the dark, Guinness afraid to speak for fear of frightening the boy with his strange English tones, until the boy got to where he wanted to go and ran off. Guinness said this incident suggested to him that there must be something justly sacred and lasting about the Catholic church. He added that the walk with the boy wasn't why he became a Catholic; it simply got his attention. But it was the story he told about how he came to the church. And unlike so many famous converts, he stayed.

It is fun to think of Guinness and his friend Graham Greene debating Catholic doctrine and Catholic folly over sherry or Scotch, but I suppose they never did. Probably both were too English, too reticent, and equally bored and embarrassed by pretension. Reading his published diaries, one sees that later in life Guinness got a bit impatient with clumsy liturgies and illiterate sermons (he said it was a relief to go to the Farm Street Church in London and experience a dignified Mass and an intelligent preacher), but just when you are about to type him as a religious or political Tory, he surprises you with an unexpected prejudice. He was not PC, in any direction.

Sir Alec Guinness remained, steadfastly, an elusive individual, hiding not so much behind his masks as the mystery and dignity he brought to his life and work. Requiescat in pace.

Keith Burris, editorial page editor of the Manchester Journal-Inquirer in Manchester, Connecticut, is writing a biography of the conductor Robert Shaw.