Fifth Avenue, 5 A.M.

In the popular imagination, the 1950s and 1960s were diametrically opposed, the rebellion of the ’60s born out of the repression of the ’50s. Everything exploded in 1968, literally and metaphorically, from Berkeley to Paris to Prague. Hollywood, too, underwent a sea change through the collapse of the Hollywood Production Code (or “Hays Code”), designed to ensure that “no picture shall be produced that will lower the moral standards of those who see it.” Its replacement by the Motion Picture Association of America’s rating system was as revolutionary as Prague Spring.

Yet like any revolution, the seeds were sown years earlier, as Sam Wasson suggests in Fifth Avenue, 5 A.M.: Audrey Hepburn, Breakfast at Tiffany’s, and the Dawn of the Modern Woman, his history of the making of the 1961 film. To claim Hepburn marks a turning point from the domestic postwar years to the ’60s, with its sexual revolutions and social upheavals, is a weighty thesis to pin on shoulders as slim as hers. Yet Wasson’s thesis works because the book is not just about Hepburn, but about the collective ambitions and anxieties that fueled the making of the film, and the shifting sociocultural context of its production.

Wasson’s story begins with novelist Truman Capote, whose heroine was inspired by his capricious mother and society “swans” like Gloria Vanderbilt and Babe Paley, whom he courted. Paley, unhappily married to a wealthy but cold husband, showed Capote that, “with wives across America financially dependent upon their husbands, being a married woman was a euphemism for being caught.” Capote’s heroine, Holly Golightly, grew out of his desire to give these women freedom and immortality. Her love interest was originally platonic – a gay man much like himself – that is, until screenwriter George Axelrod got his hands on him.

Just as America’s women, the target audience of the day, were ready to see a woman with individuality and style who was morally complex but wasn’t punished for it, Axelrod and director Blake Edwards were itching to make a romantic comedy for grown-ups.

Ironically, it is Hepburn who was the most conservative. After an engagement folded under the pressure of her career, she married Mel Ferrer, an actor 10 years her senior. Jealous of her success, Ferrer chastised her publicly when she put her elbows on the table or exhibited other “unladylike” behavior. After reading “Breakfast at Tiffany’s,” Hepburn told coproducer Marty Jurow, “You have a wonderful script, but I can’t play a hooker.”

More cosmopolitan than Doris Day but less sensual than Marilyn Monroe, Hepburn’s popular appeal blended innocence and sophistication, hinting at the sexuality forbidden to filmmakers. Her transformation in “Roman Holiday” and “Sabrina” from “good girl princess” to sophisticate, paved the way for the risqué Holly. Along the way, she sported an outré European haircut and pioneered the LBD (or “little black dress”), signaling her shift from sexual innocence to experience, and sending shock waves through the fashion world. The LBD appears in “Fifty Dresses That Changed the World,” which attributes “its most notable manifestation” to “Breakfast at Tiffany’s.”

Reading a book about a movie is seldom as entertaining as watching the film, but Wasson’s is the rare exception. His style, a “perilous path between the analytic interpretation and the imaginative one,” creates a playful tone, as does his juggling of competing story lines, a literary version of cinematic crosscutting.

Novelistic techniques like free indirect discourse enable him to slip into his characters’ perspectives, but he supports these maneuvers with documentation. His interviews are extensive. Poor George Peppard, who somehow thought “Breakfast at Tiffany’s” was all about him, gets creamed by pretty much everyone, despite Wasson’s best efforts to “give [him] a fair shake.”

The one weakness is a cursory treatment of Mr. Yunioshi, the Japanese neighbor played by Mickey Rooney, whose excruciatingly racist scenes break the otherwise note-perfect spell of the film. Wasson tells a wonderfully awkward story of producer Richard Shepherd’s chagrin when confronted later by director Akira Kurosawa, but his coverage of protests by Asian-Americans (one as recent as 2008) feels a bit thin.

Wasson’s emphasis, rather, is on the film’s impact on women, who saw themselves in Hepburn’s Holly. Letty Cottin Pogrebin, cofounder of Ms. Magazine, went so far as to claim Holly as an “alter ego”: “Here was this incredibly glamorous, quirky, slightly bizarre woman who wasn’t convinced that she had to live with a man.” The validation this gave women whose lives didn’t look like June Cleaver’s is the most lasting legacy of “Breakfast at Tiffany’s.”

Elizabeth Toohey is an English professor at Principia College in Elsah, Ill., where she specializes in postwar American culture.