Somehow he convinced Shaw to give him the rights to his plays, beginning with "Pygmalion" (1938), which he released as a film. It was an enormous international hit, both critically and financially. Pascal tried to convince Shaw to let "Pygmalion" be turned into a musical, but the outraged Shaw explicitly forbade it, having had a bad experience with the operetta "The Chocolate Soldier" (based on Shaw's "Arms and the Man"). Pascal was the only person to convince Shaw to adjust his scripts to the new medium of cinema, gaining concessions from Shaw that no one else could. Pascal created the line for "Pygmalion" (later used by Lerner and Loewe in their musical version "My Fair Lady") "The rain in Spain stays mainly in the plain." Shaw, who publicly was referring to Pascal as a genius, added the line into the script.