Across the street from where I live in Melbourne is Video-Dogs, the best DVD and video shop on the planet, if not the universe. I was browsing through treasures like the complete oeuvre of Akira Kurasawa and the best of “Twin Peaks” on Wednesday, when Spiro, the proprietor, told me that Anne Bancroft was dead.

Anne Bancroft. And we both thought of Mrs Robinson, the sexy, bored, wicked, middle-aged temptress in The Graduate, the ultimate Sixties flic. So did everyone else. Newspapers around the world ran obituaries under headlines like “Here’s to you, Ms Robinson”. Think of Anne Bancroft and you can’t help humming Simon & Garfunkel: “Coo coo ca-choo, Mrs. Robinson; Jesus loves you more than you will know, wo wo wo”.

Woe, woe, woe, indeed, for Anne Bancroft. The Graduate poisoned her career. “I am quite surprised that with all my work, and some of it is very, very good, that nobody talks about The Miracle Worker,” she said in 2003. “We’re talking about Mrs Robinson. I understand the world -- I’m just a little dismayed that people aren’t beyond it yet.”

She was right and the critics are wrong. After all, The Miracle Worker is the only film for which she won an Oscar. The Graduate is just a stale curio from the sexual revolution, while the visceral drama of this astonishing film continues to haunt me.

The Miracle Worker tells the true story of the childhood of the legendary Helen Keller. As an infant she was struck by a mystery illness which left her profoundly blind and deaf. This was 1880s in rural Alabama and medical support was almost non-existent. With her only senses taste and touch, she grew up as a clothed pet whose future was life in an asylum for “defectives”. Anne Sullivan, a 20-year-old teacher, partially sighted herself -- the character played by Bancroft -- was dispatched from Boston to tame Helen.

This is not a sentimental feel-good film. Its theme is parenting, the challenging art of reconciling doting love and unyielding discipline. In sex-addled Hollywood, the daily drama of parenting, of civilising minds and souls and bodies, is trivialised in hundreds of sitcoms and films like The Incredibles. The Miracle Worker elevates this humdrum struggle to its true place as a keystone of individual lives and all of society.

This is the story. The parents love their daughter (played by another blast from the past, Patty Duke), but can hardly bear her because of her tantrums and filthiness. The steely Miss Sullivan sets about to crush the child’s wilfulness. Unlike her parents, she dares to discipline Helen. “No pity,” she says grimly, “I won’t have it.”

Every mother and father will recognise their own hand-to-hand combat with toddlers in this epic battle. A key scene takes place in the dining room. Seven-year-old Helen is used to feeding herself by circling the table, grabbing food from the family’s plates and stuffing scraps into her grubby maw. Miss Sullivan sits her down with a napkin under her chin and thrusts a spoon into her fist. Hours later, the elegant dining room is spattered with food, the crockery is smashed, silver is strewn over the floor -- and Helen is feeding herself like a lady.

But the film makes clear that obedience is just the beginning. Good behaviour is not a straitjacket, but a liberation from ignorance and self-will. Every day, millions of parents tell this to their sulking offspring -- and both sides find it hard to believe. But the plight of the blind and deaf Helen makes it absolutely, desperately believable.

Without self-discipline the poor girl cannot learn a single word -- literally. With it, a miracle happens: she makes the startling link between her teacher’s language of signs and the things the signs signify. The coolness of water is the letters spelled onto her palm, W-A-T-E-R. She is freed by learning language.

And there the film ends, with Anne Bancroft cuddling her pupil on the steps of a Southern mansion as night falls, exhausted and happy at the beginning of Helen’s new life as an author of several books, lecturer and linguist (she learned to read French, German, Greek, and Latin in braille). And we’re exhausted, too. The Miracle Worker is remarkable cinema, the true legacy of Anne Bancroft. Every parent should watch it.

Michael Cook is editor of MercatorNet.