If you've seen the movie, you know the story (the movie is very close to the book). The milkmaid Buttercup falls head over heels in love with the farm boy Westley. When Westley leaves to earn his fortune and is reported dead, Buttercup's heart breaks and she agrees to marry Prince Humperdinck although they both know they don't love each other. When Princess Buttercup is kidnapped by a band of ruffians, a mysterious man in a black mask begins to follow them, intent on capturing the Princess. This story has it all... intrigue, swordfighting, pirates, true love, miracles, etc.
The story is fantastic and if you like the movie, you will love the book. The only thing I didn't like about this book was the gimmick that Goldman perpetuates throughout the novel, claiming that he's abridged the 1000-page volume written by S. Morgenstern. Although it works in some parts (in the movie these are the parts done by Fred Savage as he interrupts the story to ask questions or make comments), I found some of it to be long-winded and a bit boring. This edition has an extended ending which I skipped because of Goldman's verbose explanations of how he came to write it. Although the Princess Bride story has a classic feel, Goldman's narration feels dated. Someone should abridge Goldman's book. ;)