Shaw, a lifelong socialist, believed class was a social construct, easily challenged, and he used his play in part as a bully pulpit to target the rich. Thus Higgins, who might have been treated as a mere eccentric in the hands of another author, becomes a paradigm of upper-crust creepiness, capricious and bullying in his attempt to wring a duchess out of the "sodden cabbage leaf" Eliza. He presages in a lighter vein James Stewart’s Scottie Ferguson in Vertigo, though admittedly the latter’s attempt to transform the trashy Judy (Kim Novak) into the regal, mysterious Madeleine is a far more grim and vicious process. Asquith’s faithfulness to Shaw pays off beautifully here, giving full play to the author’s counterpointing of Higgins’ complex mix of genius and juvenility with Eliza’s engaging blend of innocence and street-smarts. Asquith lets the actors make the most of Shaw’s superb dialogue. Howard, for example, clearly relishes his verbal assaults on Eliza. Even in their first meeting on the street, he practically glows when referring to her "curbstone English, the English that will keep her all her days in the gutter." Later he gleefully ratchets up the insults: "She’s so deliciously low, so horribly dirty. I shall make a duchess of this draggle-tail guttersnipe." And he offers a caution that if she fails in the experiment they’ve embarked on, "Your head will be cut off as a warning to other presumptuous flower girls."

Of course, as Eliza changes, so does Higgins. Her lingering presence in his house, the first in the self-professed woman-hater’s history, inspires Higgins’ housekeeper Mrs. Pearce (Jean Cadell) to set down new rules for her employer: no swearing, no walking around in a dressing gown. Pygmalion becomes almost as much Higgins’ story as Eliza’s, as the professor’s amusement at the success of his experiment gives way to a quite unexpected melancholy at the idea of her departure from his house and his life.

In spite of his fidelity to the play, Asquith can’t be accused of merely transferring Shaw’s original to celluloid with no cinematic intervention. He handles Eliza’s transformation with aplomb in a montage that cleverly intercuts scenes of Higgins upbraiding her with otherworldly images of the bizarre accoutrements of his laboratory — a sinister laughing clown, giant plaster ears — which looks more than a little like the lair of a mad scientist. The film also brings to life scenes originally played offstage, most memorably Eliza’s second public test at a grand ball in which she meets the queen and mesmerizes everybody in sight.

One of the best scenes is the allegedly overhauled Eliza’s first encounter with a drawing room full of rich people. Still not entirely divorced from her "gutter" origins, she regales the group with absurdly stilted declarations about the weather ("In Hampshire, Hereford, and Hartford, hurricanes hardly ever happen!"), then lapses into penny-dreadful tales of murderous husbands and aunts "done in" by gin. At her second encounter, the grand ball, she’s polished to the point of muteness, and can now fool everyone with ease. Later, in a poignant moment, she renders the normally babblesome Higgins speechless when she quietly affirms her humanity at the expense of his: "I sold flowers . . . I didn’t sell myself."

Performances, always a strength in an Anthony Asquith film, are uniformly fine, but the standout is unquestionably Wendy Hiller. With one of the great faces in classic British cinema and a gravitas almost alarming in an actress only 25 when the film was shot, she evokes both the rough Eliza and the nouveau Miss Doolittle with scintillating power. Her riveting performance in Pygmalion made her an international star and the standard by which all future Elizas must be judged.