Openly gay Truman Capote's 1958 novella Breakfast at Tiffany's was unlikely movie material in the waning Eisenhower years. Its self-invented heroine, Holly Golightly, was a backwoods Alabama girl who became a free-spirited Manhattan sophisticate and expensive prostitute. She was neither redeemed nor punished for her "sinful" life. The story had no romance – the central male character was gay. Yet three years later, much altered, it became a landmark film. In the engrossing Fifth Avenue, 5 A.M., Audrey Hepburn, Breakfast at Tiffany's, and the Dawn of the Modern Woman (Harper Studio, $19.99), Sam Wasson shows how that happened, and analyzes its unforeseen impact.

The central problem, Wasson argues, was how to suggest Holly's profession without its unsavory trappings. Capote had wanted Marilyn Monroe, but she would have been too obviously a hooker. In 1960, Hollywood's real-life "bad" woman/adulteress, Elizabeth Taylor, won an Oscar playing prostitute Gloria Wandrous in Butterfield 8, but her atonement was insufficient, and she died in the last reel. Audrey Hepburn (1929-93), the era's leading romantic actress, would bring a different persona to the role. The challenge would be getting her to play it – assuming a suitable script could be written.

Wasson, in short, punchy chapters, explains how George Axelrod, author of the salacious, lowbrow The Seven Year Itch, a Broadway success but a heavily censored and plodding film starring Monroe (1955), longed to write a sophisticated, Noel Coward-type screenplay. Top directors like William Wyler, Billy Wilder, and George Cukor weren't available, or were uninterested. So Blake Edwards, best known for television's Peter Gunn, got the assignment. The producers, Marty Jurow and Richard Shepherd, believed it could be made, and campaigned to get Hepburn, who was under contract to Paramount.

Wasson recounts Hepburn's ascent to stardom, but misses her initial appeal. Citing designer Edith Head, he claims her legs were too long and her waist too small (hardly possible in a dancer). Hepburn thought her feet too big, and admittedly, her bust was modest. More surprisingly, he's critical of her face. Yet, after dancing in the chorus of the London production of High Button Shoes, she attracted attention in two revues, Sauce Picante (1949) and Sauce Tartare (50). Picturegoer magazine, noting her photogenic appeal, praised her lavishly.

In 1951, she had small parts in six British films. While making one, Monte Carlo Baby, on location, Colette spotted her. She had authorized a Broadway adaptation of her novel Gigi, but no lead had been signed. She chose Hepburn, who triumphed. Just before the opening, Hepburn tested for the runaway princess in Roman Holiday (53). Wyler and Paramount were so impressed that they waited until her Broadway commitment ended to start shooting. She would win the Best Actress Oscar and return to Broadway, earning  a Tony as Ondine, co-starring future husband Mel Ferrer.

Eventually, the producers and Edwards convinced Hepburn to play Holly. A very insecure actress, she needed strong, patient directors – she required many retakes. She was, however, the consummate professional – kind, thoughtful, generous, with virtually no star ego. Ferrer had a huge and generally negative influence on her. As her career took off, his faded. He was controlling and publicly critical of her.

Axelrod's script turned the gay narrator into Paul Varjak, a gigolo and novelist, well-played by handsome but difficult George Peppard. This made them equal – both were having sex for money. Patricia Neal, superb as the woman keeping Paul, makes his profession very clear, while Holly's is handled more subtly.

Hepburn's wardrobe was also crucial. Her clothes for Roman Holiday had been designed by Paramount's Head, but while filming her second Hollywood picture, Sabrina (54), Hepburn met Hubert de Givenchy, and together they made fashion history. Over Head's objections and life-long resentment, he designed Hepburn's clothes from then on, including the famous black dress Holly wears. Head's jealousy explains her criticisms of Hepburn's figure. Givenchy's deceptively simple creations emphasized Hepburn's height, her elegant neck, and showcased her superb carriage.

Wasson writes that women identified with Hepburn in ways they couldn't with Monroe or Taylor, but he's mistaken. Like them, Hepburn was unique, and audiences knew it. Witness the parade of  Monroe wannabes, like Jayne Mansfield and Mamie Van Doren; Joan Collins was called "the poor man's Elizabeth Taylor." Hepburn had no imitators.

He's at his best, however, in describing the impact Hepburn's free-spirited Holly had. He's right that she was a new heroine, perhaps the daughter of a pre-Production Code woman that Hollywood celebrated in the early 1930s. Like them, she was independent. She didn't care what others thought. She was funny and sexually adventurous. She wasn't as hard as they were – her romantic nature conflicts with her practical, materialistic goals. True, Hepburn is an unlikely ignorant rural girl, but enchanted viewers were so dazzled by her that they accepted her origins.

Wasson's judgment about Hepburn's post-Tiffany films is flawed. He underestimates the effectiveness of Charade (1964) and her sexiness in How To Steal a Million (66). But he's right that Two for the Road (67) is her finest romantic comedy and probably her greatest performance. Disagreeing with an informed and sympathetic writer about Hepburn makes this book compelling – Wasson challenges the reader. Authors don't do that often enough.