Tennessee Williams is still looking like one of the greatest playwrights of the twentieth century and the plays he wrote from The Glass Menagerie in 1944 to The Night of the Iguana in 1961 with The Milk Train Doesn’t Stop Here Anymore as a weird rider are the greatest dramatic body of work since Eugene O’Neill and in fact surpass him, just as they surpass Arthur Miller even if Death of a Salesman and The Crucible are classics that seem to define an era and have an unsurpassable power of dramatic effect in their evocation of Willy Loman, the little man who falls like a Titan, and the Salem witch trials as paradigms of unreason and political infamy.

Think of the plays that rival it: Menagerie with its suffocating mother and isolated wan girl with her animals and the troubled voice of Tom, Hamlet-like in his self-interrogation. Think of Cat On a Hot Tin Roof with Paul Newman and Elizabeth Taylor and Burl Ives as Big Daddy. Even when the films are bowdlerised they bequeath to us the legacy of Williams’ idiom. Newman also did Sweet Bird of Youth with Geraldine Page as the old star. You can argue about particular instances of Williams – Katharine Hepburn didn’t like the way Suddenly, Last Summer had turned out – remember the girl (Liz Taylor) with the lobotomy, the horrific fate of the son (Montgomery Clift) but there’s a full and rich version from the BBC with a cast led by Maggie Smith.

When Night of the Iguana hit the Broadway stage it was with the great Bette Davis who had not appeared on a stage in decades and was not at her most comfortable with the medium. It’s the film version by John Huston with Richard Burton as a catastrophe of a priest who organises travel tours to Mexico and Ava Gardner as the raw old flame we heads towards which rivets the mind with a sense of wonder at its weirdness and its palpable plea for those who will forever fear the loss of an integrity they forever fumble towards as the enigmatic touch of the breath of God or whatever good can be guessed at as a hypothesis of hope.

Burton’s priest hits the bottle and tries to stay straight in the face of Sue Lyon’s athletically ribald underaged teen and John Huston films Kubrick’s Lolita with a tangible feeling for her attractiveness that sounds its own warning bell in this lustrous anti-pastoral of a film shot in the ravishing vicinity of Puerto Vallarta and the hotel nearby. It made Burton and Taylor buy a house there and the dark idyllic vision, at once lyrical and at the constant knife-edge of despair, makes Night of the Iguana a strange madcap black comedy which is at the same time at the edge of romance in the Shakespearean sense. Anything can happen. Gardner’s husband recently died and she dallies with Mexican beach boys who are all pluck and perdition as they toy endlessly with the grace and grotesquerie of the strange iguana lizards confined by the strings that keep them in prison until some hand of charity cuts the string.

And the fumbling hands of charity are omnipresent in this tragi-comic scribble of a play which is full to overflowing with the black magic of human hope in extremis. Burton is being pursued (and in practice persecuted) by a cheerleader figure who leads the busloads of old biddies in choruses of ‘Keep your sunny side up’ – or whatever – even as she relentlessly accuses him of dallying with Lyons though there is a weird late scene when he has mercy on her for her own implicit sapphic side.

But it’s all like that in Night of the Iguana. The play is like a postcard of hypothetical purgatories and it burns and soars through every potential crucifixion of the heart that the spirit of comedy (which is as much the spirit of consolation as it is that of contradiction) can hurl at dramatists supreme or imperfect. In the midst of the rabid tour bus farce there is the apparition of Deborah Kerr as a ladylike spinster from Nantucket and her 97-year-old poet grandfather who is subject to strokes and who is also transported to quote line after line of rhyming verse which he may or may not have written decades before. Kerr paints portraits and they are desperately poor but not – or not quite – in spirit.

Through all this swerving and zigzagging in the very mouth of catastrophe there is Ava Gardner who loves Burton like the sun, who gives to him absolutely with the irresistible lapping of the waves, with the warmth of the sun. Gardner’s is the greatest performance in the all-but-lost treasure garden of this film which is jewel-like in the precision and richness of its central performances. Richard Burton is magnificent with his Shakespearean grandeur just slightly muffled like an actor who is scared of losing his soul if he can’t remember Hamlet’s lines or the moral imperatives which make him more than just a sinner because he knows he is one. Deborah Kerr captures the very precise moral courage of a woman who realises the eternal virginity of the soul – was that Yeats’ phrase? – is a new heaven and a new earth. It’s a performance poised between Noel Coward and Chekhov but Kerr never allows the performance to seem less than real.

You can say this is a late play. It has the riskiness of a great dramatist pleasing himself to construct his weird magical gambits that work because the drama that propels them is real in the face of all improbability.

John Huston directs it like an absolute master. The touch is consistently light to the point of being skipping but it is replete with a full-blooded passion for both existential parables and the lace-like beauty of grey light as well as the dances and diversions of darkness.

Night of the Iguana is a very beautiful film, a kind of allegorical cartoon that has the power of compassion that is its trump card. You can see it for $4.29 on Amazon. It makes most contemporary film look like the work of children.