To write a wonderful story or a gripping play, look to the legends. George Bernard Shaw took the legend of Pygmalion and turned it into "My Fair Lady", a hit musical and movie.
What is the legend of Pygmalion? Pygmalion was a sculptor who fell in love with a statue that he himself had carved. That's the Greek legend.
Now look at how cleverly Shaw turned that legend into a teacher of speech "sculpting" a "block of stone" - Pygmalion is Professor Henry Higgins, who teaches speech and the "block of stone" is Eliza Doolittle. Higgins teaches (sculpts) Eliza on a dare but falls in love with her, his own sculpture.
Once you have that complication, you have the plot and the freedom to make your own end to the play.