Pygmalion is a comedy about a phonetics expert who, as a kind of social experiment, attempts to make a lady out of an uneducated Cockney flower-girl. Although not as intellectually complex as some of the other plays in Shaw's "theatre of ideas," Pygmalion nevertheless probes important questions about social class, human behavior, and relations between the sexes.

Hoping to circumvent what he felt was the tendency of the London press to criticize his plays unfairly, Shaw chose to produce a German translation of Pygmalion in Vienna and Berlin before bringing the play to London. The London critics appreciated the acclaim the play had received overseas, and, after it opened at His Majesty's Theatre on April 11, 1914, it enjoyed success, firmly establishing Shaw's reputation as a popular playwright.

Accompanying his subterfuge with the London press, Shaw also plotted to trick his audience out of any prejudicial views they held about the play's content. This he did by assuming their familiarity with the myth of Pygmalion, from the Greek playwright Ovid's Metamorphoses, encouraging them to think that Pygmalion was a classical play. He furthered the ruse by directing the play anonymously and casting a leading actress who had never before appeared in a working-class role. In Ovid's tale, Pygmalion is a man disgusted with real-life women who chooses celibacy and the pursuit of an ideal woman, whom he carves out of ivory. Wishing the statue were real, he makes a sacrifice to Venus, the goddess of love, who brings the statue to life. By the late Renaissance, poets and dramatists began to contemplate the thoughts and feelings of this woman, who woke full-grown in the arms of a lover. Shaw's central character—the flower girl Liza Doolittle—expresses articulately how her transformation has made her feel, and he adds the additional twist that Liza turns on her "creator" in the end by leaving him.

In addition to the importance of the onginal Pygmalion myth to Shaw's play, critics have pointed out the possible influence of other works, such as Tobias Smollett's novel The Adventures of Peregrine Pickle (which similarly involves a gentleman attempting to make a fine lady out of a "coarse" working girl), and a number of plays, including W.S. Gilbert's Pygmalion and Galatea and Henrik Ibsen's A Doll House. Shaw denied borrowing the story directly from any of these sources, but there are traces of them in his play, as there are of the well-known story of Cinderella, and shades of the famous stories of other somewhat vain "creators" whose experiments have unforeseen implications: Faust, Dr. Frankenstein, Svengali.

The play was viewed (thankfully, by many critics) as one of Shaw's less provocative comedies. Nevertheless, Pygmalion did provoke controversy upon its original production. Somewhat ironically, the cause was an issue of language, around which the plot itself turns: Liza's use of the word "bloody," never before uttered on the stage at His Majesty's Theatre. Even though they were well aware of the controversy from its coverage in the press, the first audiences gasped in surprise, then burst into laughter, at Liza's spirited rejoinder: "Not bloody likely!"