In this narrative, the Big Friendly Giant (BFG) transports his companion to a mysterious, ethereal landscape known as "Dream Country." Described as a place of "swirling mists and vapours," it serves as the origin point for all dreams. The BFG emphasizes the need for absolute stealth, instructing his companion to stay "as still as winky little mices" and to "stop breathing" to ensure they can capture the dreams without disturbance. The BFG’s sensory perception is remarkable; he describes his ears as "swiveling out of his head" to catch the dreams, which he identifies with whimsical terminology such as "fizz wizards" and "golden fizz wizards."
The mission takes a dark turn when the BFG catches a particularly volatile entity. Instead of a pleasant dream, he captures a "truck lump," which he quickly identifies as a "real kicksy bog dumper." This is no ordinary dream; it is a "bad, bad dream" or, more accurately, a "nightmare." The BFG notes that "the nastier the dream, the angrier it is getting when it is in prison," highlighting the danger of the specimen trapped within the jar. The intensity of this "struggle-hunting, bug-thumping grub-switcher" is so unsettling that the BFG decides to terminate the day's dream-catching expedition prematurely.
Upon returning to the "hot yellow wasteland" where the other, more malevolent giants are sleeping, the BFG conceives a "wopsy shifling idea." He decides to use the captured nightmare as a weapon against the "flesh lump eater." Despite his companion's initial hesitation, the BFG loads the "terrible nightmarish chocolate humper" into his trumpet and blows it into the ear of the sleeping giant.
The effect is immediate and chaotic. The nightmare induces a vivid hallucination in the giant, who begins to scream in terror, believing he is being attacked by "Jack." The BFG explains that Jack is the only human all giants fear, known as a "famous giant killer." The giant’s terror is palpable as he cries out, "Jack is whack-crackling me" and "Jack is spike-sticking me," begging for mercy from the imaginary "terrible spike-sticking beanstalk."
The nightmare triggers a massive brawl among the sleeping giants. As the giant "punched the meat dripper straight in the mouth" and the others wake up to join the fray, the BFG observes the "tough and rumble" with a sense of satisfaction. While the companion describes the other giants as "foul and filthy," the BFG remains unbothered, knowing the giants are accustomed to "bishing and walloping at one another." The episode concludes with the BFG successfully weaponizing a nightmare to turn the giants against each other, proving that even in the world of giants, a well-placed dream can be more powerful than brute force.