Don Juan DeMarco
The movie is based on two different sources; the modern-day story is based on director/screenwriter Jeremy Leven's short story "Don Juan DeMarco and the Centerfold" ( the movie's original title before the studio changed it shortly before release ) , while the flashbacks depicting DeMarco's back-story are based on the more familiar legend of Don Juan , especially as told by Lord Byron in his version of the legend . 
<triplet> Don Juan DeMarco <subj> Jeremy Leven <obj> director <triplet> version of the legend <subj> Lord Byron <obj> author