A young boy is home sick in bed, and his grandfather comes to read to him. The book is called The Princess Bride, and the boy expressed doubt that it will be any good, but his grandfather assures him it’s full of really good stuff, such as fencing, fighting, chases, escapes, miracles, and true love. They settle in to read.

The story begins with a young woman, Buttercup, who lives on a farm in a medieval setting. She loves riding her horse and bossing around the hired hand, a young man named Westley. Every demand she makes of him he responds with a simple, “As you wish.” One day she realizes that every time he says this, he’s really saying, “I love you,” and she realizes she loves him as well. Westley sets off to make his fortune, promising her that he will always come for her. Several weeks later Buttercup receives the news that Westley had been murdered by the Dread Pirate Roberts, and she vows never to love again.

A few years later, Prince Humperdinck has chosen Buttercup to be his bride, even though she tells him she will never love him.

One day while she is out riding, Buttercup is kidnapped by three men who plan to murder her in order to start a war. As they make their way with her, the leader, Vizzini, notices a strange man dressed in black who is following them. Vizzini dispatches his swordsman, Inigo, to kill him, but there is too much mutual respect between the two, and the man in black merely defeats Inigo in a swordfight and continues. The same thing happens when Vizzini tries to have Fezzik, his gentle giant, kill the man. Finally the man in black has a battle of wits with Vizzini himself as he holds Buttercup at knifepoint. He tricks Vizzini into drinking poisoned wine and frees Buttercup. The man in black reveals himself to be the Dread Pirate Roberts, and Buttercup, in a fury at the man who murdered her love, pushes him down a hill, telling him “You can die too for all I care!” As the man falls down the hill, she hears him cry out, “As you wish!” and she realizes it’s been Westley the entire time.
Westley and Buttercup reunite at the bottom of the hill, and escape into the Fire Swamp as they are being pursued by Prince Humperdinck and his second in command, Count Rugen. They make it through alive, but the men are waiting for them on the other side. Rather than lose Westley again, she makes a deal with Humperdinck that she will wed him if he allows Westley to go free. The prince agrees but secretly has Rugen imprison him in the Pit of Despair.

Buttercup eventually realizes she loves Westley too much and cannot marry the prince, and the prince agrees to send a message to him so they can be together. However he sneaks off to the Pit of Despair (where Rugen has been torturing him) and kills Westley. Meanwhile Inigo and Fezzik have reunited, and Inigo has discovered that Count Rugen is the man that murdered his father so many years ago. The two search for the “man in black” to aid them on their quest, only to find him dead in the Pit of Despair. They take his body to the miracle man, Max, who declares Westley only “mostly dead” and gives them a pill to bring him back to life. The three head to the castle where Buttercup and Humperdinck’s wedding is about to take place.
The three enter the castle, and Inigo, after a vicious swordfight where he sustains several wounds, kills Count Rugen. Westley finds Buttercup and intimidates Humperdinck so badly he is too afraid to fight him, and the three men plus Buttercup escape and live “happily ever after.”
The movie ends with the grandson asking his grandfather to come back and read to him some more tomorrow, and the grandfather states, “As you wish,” with a smile.