My Fair Lady was a musical based on George Bernard Shaw‘s 1913 play Pygmalion, with book and lyrics by Alan Jay Lerner and music by Frederick Loewe.
In the play Eliza Doolittle, a Cockney flower girl takes speech lessons from a phonetics professor named Henry Higgins in order to pass as a lady.
The original Broadway and London shows starred Rex Harrison and Julie Andrews.
The musical’s 1956 Broadway production was a major critical and popular success. It set a record for the longest run of any musical on Broadway up to that time.
Source: Wikipedia
In 1964 a popular film version starred Audrey Hepburn and Rex Harrison.