The grandfather (PETER FALK) of a sick boy (FRED SAVAGE) comes to visit, bringing with him a book called "The Princess Bride," sitting down to read it to the boy who at first doubts its value, but gets increasingly involved, even to the point of calling the grandfather on certain plot points that shouldn't happen.
The story itself has at its center a girl named Buttercup (ROBIN WRIGHT) who enjoys ordering around the farm boy Westley (CARY ELWES), who accedes to her every command with a simple "As you wish." They fall in love and because he doesn't have enough wealth to marry her, Westley goes out on the seas to make some money and is kidnapped by the unseen Dread Pirate Roberts. Five years pass and Buttercup agrees to marry Prince Humperdinck (CHRIS SARANDON), royalty in the country of Florin, never giving up hope that her Westley is still alive.
Amidst all this, Buttercup is kidnapped by a scheming man named Vizzini (WALLACE SHAWN) and his two cohorts, the vengeful Inigo (MANDY PATINKIN) and the enormous Fezzik (ANDRE THE GIANT), both of whom make up brains and strength, though not according to Vizzini. The story weaves and twists, as Vizzini and Fezzik contend separately with the mysterious, yet skilled and quick-moving Man in Black, and there's also the Cliffs of Insanity, the Fire Swamp, the Pit of Despair, and the usual spate of evil doings.