There's a lot of negative things been said about Audrey Hepburn's interpretation of the role of Eliza. Perhaps she's not ideal in the earliest scenes of the movie - her "dirtiness" is never quite believable - but it has to be said that despite this smallish drawback she still glows, and makes an amazing Eliza overall.
The reason for this is simple; Audrey Hepburn brings her "own spark of divine fire", (to quote Higgins) to the role and her vulnerability, mixed with her sweet, naive charm and even her wonderfully juvenile pettishness shown in "Just You Wait" all prove what a talented actress she really is. For an example of this, just watch Eliza's facial expression at Ascot, when she realises her opportunity to demonstrate her new-found mastery of the English tongue - sweetly hilarious.
MFL has been criticized as being too romanticized, too overblown. I disagree; musicals are suposed to be lavish affairs, and none pull it off quite so well as "My Fair Lady" does. It's a momentous film but it has its subtle points: watch the way in which Eliza's eyes are centred on Higgins when she enters at the ball, and the way in which the two of them stare at each other for a few seconds at the top of the stairs a few moments later.
It musn't be overlooked that, thanks to its being based on a Bernard Shaw play, "My Fair Lady" has what the great majority of musicals lack: a deeper meaning and something really quite profound to say.
The actor in the role of Colonel Pickering is a little weak, but it must be said that Rex Harrison IS Henry Higgins. In a lot of ways (in fact, in most ways) Higgins has an objectionable personality: rude, snobbish, impatient and even misogynistic, but somehow Rex Harrison pulls it all off and makes us like Higgins without betraying the character. As to romance, his song "I've Grown Accustomed to Her Face" is an ode to the kind of love which sneaks up on you. Overall, this movie is romantic, but not too sentimental. It has just enough romance to be dramatically fulfilling, but it never becomes soppy or mawkish. The word "love" is never mentioned at all and the two leads never even kiss. The famous end sequence is perfect and does the movie justice; after all, a big happy bow tied around a perfect romance at the end would simply not fit with everything we have learned about the two protagonists.
