Classical music-loving proto-punk Alex (Malcolm McDowell) and his "Droogs" spend their nights getting high at the Korova Milkbar before embarking on "a little of the old ultraviolence," such as terrorizing a writer, Mr. Alexander (Patrick Magee), and gang raping his wife (who later dies as a result). After Alex is jailed for bludgeoning the Cat Lady (Miriam Karlin) to death, Alex submits to the Ludovico behavior modification technique to earn his freedom; he's conditioned to abhor violence through watching gory movies, and even his adored Beethoven is turned against him. Returned to the world defenseless, Alex becomes the victim of his prior victims, with Mr. Alexander using Beethoven's Ninth to inflict the greatest pain of all.

With ornate imagery reminiscent of paintings from the story's 18th century period, Stanley Kubrick's adaptation of William Makepeace Thackeray's novel depicts the rise and fall of a sensitive rogue in the British aristocracy. Young Irishman Redmond Barry (Ryan O'Neal) leaves home to seek his fortune after apparently killing an English officer in a duel. Through a series of mishaps and accidents, Barry winds up fighting with the Prussian army in the Seven Years' War under the command of Capt. Potzdorf (Hardy Kruger); at war's end, Potzdorf enlists Barry to spy on a shady Chevalier (Patrick Magee). Instead, Barry joins up with the Irish Chevalier to flee Prussia and live as gamblers among Europe's elite.

This film crystallizes the experience of the Vietnam War by concentrating on a group of raw Marine volunteers. Based on Gustav Hasford's novel, The Short Timers, the film's first half details the volunteers' harrowing boot-camp training under the profane, power-saw guidance of drill instructor Sgt. Hartman (R. Lee Ermey). Part two takes place in Nam, as seen through the eyes of the now thoroughly indoctrinated marines.