Often called the greatest of all stage musicals, “My Fair Lady” is often curiously underrated as a movie.

Curious in that the 1964 film won seven Academy Awards, including Best Picture — yet it is frequently excluded from lists of best movie musicals.

Perhaps that’s because it is generally associated with the stage — or, perhaps, because the movie production was overshadowed by a huge casting controversy.

The film will be shown this weekend at Hoquiam’s 7th Street Theatre as part of its Silver Screen Classics series.

Viewed on its own terms more than 50 years after the fact, most of the play’s virtues also apply to the film. Certainly, it was more successful and less stagy than such stage-to-screen translations of the era as “The King and I,” “South Pacific” and “Gypsy.”

Both play and movie combine some of the greatest show tunes ever composed, from the team of Frederick Loewe and Alan Jay Lerner, with an unusually strong story by musical standards. The latter was adapted by Lerner from George Bernard Shaw’s non-musical play “Pygmalion.”

Henry Higgins, a haughty London-based professor of linguistics, bets his friend Col. Pickering that he can teach the uneducated Cockney flower girl Eliza Doolittle to speak well enough to impersonate a duchess. Seeking to improve the quality of her life, Eliza takes him up on the offer and undergoes months of training.

The plan succeeds — it wouldn’t be much of a story if Higgins threw up his arms after two hours and said, “Well, I was wrong. She’s hopeless.” But the transformation causes unexpected changes in the lives of all concerned.

The Broadway version featured Rex Harrison as Higgins, Julie Andrews in her star-making role as Eliza, and British character actor Stanley Holloway as her ne’er-do-well father, Alfred Doolittle.

After acquiring the film rights, Warner Brothers studio chief Jack Warner (who produced the movie himself) envisioned a cast led by Cary Grant, Audrey Hepburn and James Cagney. But Grant and Cagney rejected Warner’s offers (Grant supposedly saying he wouldn’t even watch the movie if Harrison wasn’t cast), so Harrison and Holloway were asked to reprise their Broadway roles.

But Warner was adamant that Andrews, who was preparing for her big-screen debut in Walt Disney’s “Mary Poppins,” lacked sufficient star quality for the film. He was reportedly preparing to offer the role to Elizabeth Taylor if Hepburn declined.

Hepburn didn’t decline and, by most objective standards, triumphed in the non-musical aspects of the role. Playing a would-be duchess was easy for the always elegant actress, but she was also surprisingly convincing as a guttersnipe.

No match for Andrews as a singer, however, Hepburn had those vocals dubbed by future Seattle kids’ show hostess Marni Nixon.

This outraged devotees of the Broadway production, including Lerner. In a backlash that seems excessive if not small-minded today, Hepburn was excluded from the Academy Award Best Actress nominations — with the Oscar going to Julie Andrews for “Mary Poppins.”

Displaying a shred of humanity beneath his character’s self-absorbed, misogynistic exterior, Harrison earned the Best Actor award. Holloway was also nominated in the Supporting Actor category — although I, for one, would have loved to see Cagney take a crack at the role.

The acting is something of a bonus for a production that provides a succession of show-stopping songs (“I Could Have Danced All Night,” Wouldn’t it be Loverly,” “Get Me to the Church On Time,” etc.).

With one possible exception, veteran director George Cukor staged the numbers well, betraying little hint of the story’s stage origins.

Although a fine actor who later played Sherlock Holmes on public television, Jeremy Brett lacked the singing voice to play Eliza’s lovestruck suitor, Freddy Eynsford-Hill, and his character’s dubbed version of “On the Street Where You Live” might be disappointing to those who remember Vic Damone’s or Andy Williams’ hit recordings of the number.

As more than one critic has noted, “My Fair Lady” is an extremely unconventional play.

It is a musical that allows its lead actor to talk his way through the lyrics — an accommodation of Harrison’s limited vocal range. It’s also a comedy with serious overtones and a romance of sorts, although there isn’t anything close to a conventional love scene. The latter quality allowed Harrison to continue playing Higgins into his mid-70s, in a Broadway revival.

That revival, incidentally, also was well-received. On stage or screen, “My Fair Lady” always seems to work.