Johnny Depp plays John deMarco, a young man who lives in a dream world of his own.  One in which he is Don Juan, the greatest lover in the world, searching for his Donna Anna.  Marlon Brando plays the psychiatrist, Dr Jack Mickler, who has to try to bring John back into the real world.  Dr Mickler starts out by being amused at John's fantasies, but is soon captivated by them and even becomes part of them.

Johnny Depp plays Raphael, just out of prison, with a young family to provide for and no prospects.  He lives in a shanty town by the town rubbish dump, which is due to be demolished, leaving his family homeless.  In desperation, he turns to McCarthy, played by Marlon Brando, who makes "snuff" movies.  McCarthy offers Raphael more money than he has ever seen.  In return, Raphael agrees to be tortured to death, on camera.  Despite the sinister aspect of his character, McCarthy shows a certain sympathy for Raphael, while tempting the young "three time loser" to suicide.