Once the royal marriage logistics are underway, Buttercup is brought into the Great Square to meet her subjects as Prince Humperdinck's bride-to-be. She walks among the people and they all adore her—or so we are led to believe until she is kidnapped by three of her subjects while she is in the forest, riding her horse. The three men, Vizzini, Fezzik, and Inigo Montoya, take her onto a ship and discuss their mission to kill her to start a war between Guilder and Florin. She is quite frightened, as one might imagine, so she leaps into the sea. Sharks surround her and when the moon lights up the dark sky, Fezzik pulls her back onto the boat. At this point, the narrator interrupts to reassure us that she does not die here: "Well, since the book's called The Princess Bride and since we're barely into it, obviously, the author's not about to make shark kibble of his leading lady."
Around this time, Inigo notices a ship following them toward the Cliffs of Insanity, and Vizzini dismisses it as inconceivable. Yet the black ship behind them gains, and our three bandits and their stolen princess scale the cliffs on a rope draped around Fezzik's enormous body, and they arrive at the top to see that a man in black is following them up. At the top, Vizzini unties the rope, and to everyone's astonishment, the man does not fall, but rather climbs with his hands. This merits another "Inconceivable!" from Vizzini, who them instructs Inigo to kill the man in black and promptly darts away with Fezzik and Buttercup in tow.
The narrative includes a flashback history into Inigo's childhood. We learn that he and his father, Domingo Montoya, lived high in the hills of Spain, where his father grudgingly and surreptitiously made back-order swords for Yeste, the most famous Madrid sword-maker. One day a six-fingered count, Count Rugen, approached and requested a special sword, and Domingo spent a year slaving over this, his magnum opus, only to have the Count return, refuse to pay its full price, and promptly kill Domingo. Inigo, a boy at the time, left his village and learned everything he can about sword fighting to seek his revenge, and soon was declared by Yeste to be a wizard, the highest rank in steel. But unable to find the six-fingered count, Inigo soon lost steam and became a drunkard, the state in which he was found and employed by Vizzini.
We return to real time, where an impatient Inigo helps the man in black up to the top of the cliffs. They duel, accompanied by a fantastic description of technique and terrain. Both begin with their left hands and switch to their right once they tire, demonstrating even further their high and matched abilities. Finally the man in black wins, but instead of killing Inigo he simply knocks him out with the butt of his sword, and then runs off in pursuit of the princess. Vizzini espies the man in black running toward them and is astonished, so he leaves Fezzik to dispose of him at last.
Here we have a flashback history into Fezzik's childhood, and we learn that his parents encouraged him to use his strength and size (he was an extremely large Turkish baby) to discourage his classmates from bullying him. Fezzik, a tearful and worrying child, did not want to fight but obeyed his parents anyway, and soon he had defeated all of the strongest men in Turkey. He moves through Greece, Korea, and time after time the audience booed Fezzik because the ease with which he fought made the competition seem unfair. Soon he began fighting gangs, since individuals were too easy. After Fezzik's parents died, he was left alone and lonely in Greenland where he comforted himself with rhymes until Vizzini found him. As unpleasant as he is, Vizzini did serve as the ministering angel for both Fezzik and Inigo.
Back near the Cliffs of Insanity, Fezzik challenges the man in black to a wrestling match, and unbelievably the man in black wins by clinging to Fezzik's neck and blocking his windpipe. The man in black leaves Fezzik alive, but barely, and he runs off to seek Vizzini, who is waiting at a picnic area with Buttercup. Thus ensues the famous Battle of Wits, where the man in black places iocane powder in wine and waits for Vizzini to choose which glass is left unpoisoned. Through a winding jigsaw process of reasoning, Vizzini examines the situation from many angles, switches the goblets while the man in black was distracted, and drinks from his own goblet. He dies laughing at how cleverly he fooled the man in black.
The man in black unties Buttercup and releases her blindfold, explaining that in fact both cups were poisoned because he had made himself immune to iocane powder. Buttercup is quite frightened, begs him to release her, and ultimately is forced to run with him along the Guilder terrain. Soon Humperdinck's armada approaches, and the man in black questions Buttercup about his hunting techniques, then about the coming marriage. He accuses her of frigidity and inability to love, and she glowers at him and pushes him into the adjacent ravine. As he falls, his voice carries up to her ears, a faint, "As you wish," and of course she then realizes that the man in black is in fact Westley, so she throws herself down after him.
Here the narrative focuses on Humperdinck. Humperdinck arrives at Guilder and recreates the battles of steel, strength, and smarts from just tracks, scents, and remnants—demonstrating his incredible hunting prowess. He continues following tracks and understands that his princess bride has been led by her kidnapper onto the ravine floor, which leads dead into the Fire Swamp, a frightening place.
The narrative switches back to the lovers, Westley and Buttercup. "S. Morgenstern" steps in to say that he feels unfair giving a descriptive account of the reunion between Westley and Buttercup, and William Goldman then steps in, saying how unfair he finds this. He proceeds to explain that he wrote his own reunion scene but his editor refused to let it in the book, and he gives a New York address and encourages readers to write in to request it. We are told that there were tears, embraces, and soon an argument during the reunion, but this is all the eavesdropping we are allowed. Buttercup and Westley enter the Fire Swamp and quickly encounter its three terrors. The flame bursts are a cinch. The Snow Sand almost drowns Buttercup, but Westley rescues her. The Rodents of Unusual Size attack them but are quickly burnt to a crisp when Westley rolls them into a flame burst.
During these adventures, Westley explains how he lived through the Dread Pirate Roberts attack. He survived because he asked for his life and proved his usefulness to Roberts, so that finally the pirate retired and turned the ship and name over to him. The name was quite an important inheritance—we learn that it has been passed from man to man over the past fifteen years to inspire the necessary fear in the plundered ships. The lovers finally exit the forest, but instead of having a clear path to Westley's pirate ship, they are met by Humperdinck and his cronies, who demand that they surrender. Buttercup quickly agrees after making Humperdinck promise not to hurt Westley. She chooses life without love over death with love, leaving Westley to Count Rugen's evil devices and disposal.
This long chapter possesses a more epic nature than any of the others. All the basic elements are here: the princess is saved from a loveless marriage by a band of murderous kidnappers, then saved from the kidnappers by the love of her life. The savior is godlike in his abilities to best the best in each field of heroism: leaned skill, strength, intelligence, and everything seems fine until the loveless husband reappears to claim his wife. This is when the heroine slips, choosing life over love. This chapter contains the bulk of the book's adventure, as well as important notes on the histories of the main male characters.
We learn the full dynamic among Vizzini, Fezzik and Inigo, and the histories of the latter two characters give us insight into the reason beneath this dynamic. Vizzini is calculating and heartless and rather pitiful; Fezzik is laden with self-doubt and a certain awkward fear; Inigo is quiet, pensive, fair. Together they stand as allegories, each the best in the world at his specific skill, posing a daunting obstacle course for Westley, who bests them all, showing himself to be a truly remarkable individual. We now know why Buttercup loves him.
As for Buttercup, we see how she has been shaped by her training and isolation. She is quieter, sadder, more beautiful, and also at times bolder than she has ever had to be before, and when she pushes Westley down to the ravine as a punishment for mocking her heartache, we see also why Westley loves her. But she has hardened, lost much of her faith in love, and she breaks the entire crescendo of the story by returning to Humperdinck. The princess bride has blown her shot at love and happiness.
Many myths are demystified in this chapter as Westley peels away their intimidation tactics and defeats them. The Dread Pirate Roberts, once the terror of the sea, has fallen into Westley's palm once he revealed the extent to which must live. The Fire Swamp, though eerie, is manageable, and inside is ultimately safer than out, where Humperdinck and his men await the lovers. The reversals in this chapter are quite impressive, as nothing is done in its proper order: Inigo rescues the man in black from the cliffs before he attempts to kill him; and Westley abuses Buttercup before he reveals himself as her beloved. Everything is explained, and none of it is conventional.