‘‘I’ve gotten into watching old movies on TCM,’’ Jennifer Lee, co-director of ‘‘Frozen,’’ told me. ‘‘And what kills me is the female characters are fantastic, complicated, messy, and they aren’t oversexualized, and I love them.’’ Actresses were second-class citizens then too, but at least they had juicy parts. The dictatorial and crass Hollywood moguls actually cared about art. They would take all the literary best sellers, throw starlets into them and make prestige movies.

Although the pioneers’ names have been forgotten in modern Hollywood, female filmmakers started out with gusto. Alice Guy Blaché, who worked as a secretary to Léon Gaumont, a Frenchman who sold cameras and film, picked up a camera in 1896 and helped invent narrative filmmaking in France and Hollywood. ‘‘It is true that I passed for a phenomenon,’’ she wrote in her memoir, adding that she knew it was an ‘‘unfeminine’’ career but didn’t care. In 1910, she became the first woman to found and run her own film studio, along with her husband and a partner. Over her career, she would oversee nearly 750 films, including cross-dressing comedies, movies playing with the gender roles in marriage and action films featuring heroines.

In 1914, Lois Weber, who was mentored by Guy Blaché, became the first American woman to direct a full-length feature, ‘‘The Merchant of Venice,’’ in which she also starred as Portia. Infused with the conviction that film could change culture, she made movies about contraception, capital punishment and poverty. She ran a production company with her husband’s help, but he often deferred to her judgment. She had great taste and said her ideal picture entertainment was ‘‘a well-assorted shelf of books come to life.’’

Dorothy Arzner, a screenwriter and director who worked in Hollywood from 1922 to 1943, had her technicians rig a microphone to a fishing pole, essentially inventing the boom mike. She helped Katharine Hepburn get her start and still has the largest body of work by a woman director. ‘‘No one gave me trouble because I was a woman,’’ she said in 1974. ‘‘Men were more helpful than women.’’ The veteran director Allison Anders tells boom operators on her projects that their jobs were created by a woman.

So given such remarkable trailblazers, how did women in Hollywood start reeling backward?

The more I talked to people, the clearer it became that if the luminous Hollywood of my childhood was obliterated for good, it all started with ‘‘Jaws’’ in the summer of 1975, which would devour half a billion dollars at the box office. America fell in love with the blockbuster, and Hollywood got hooked on the cohort of 15-year-old boys. It has never wavered in this obsession, even though girls and women buy half the movie tickets and watch more TV series, and even though teenage boys are increasingly fixated on gaming.

In the ’80s, the paradigm that ‘‘Jaws’’ helped create shifted yet again. Studios began being swallowed by conglomerates, and as Norma Desmond predicted, the picture business became small. Box-office revenues would eventually go from 70-30 domestic/international to 30-70, which meant foreign markets were calling the shots. Dialogue and women who weren’t in leather cat suits became superfluous. Crunching data, foreign sales companies started providing the presale estimates for the value of a movie and its stars outside the United States, and producers would borrow money against those estimates. They often want the male players attached before the female ones because men tend to have more value in foreign sales. ‘‘The moment you mention it’s a female director to foreign companies, you can see the eyes roll,’’ said one woman leading a studio. ‘‘Buyers want action films, and they don’t see women as action directors.’’