Spoiler alert: Emma Stone and Steve Carell’s screen version of the “Battle of the Sexes” is almost as exciting and certainly as entertaining as the original tennis match played by Billie Jean King and Bobby Riggs in the Houston Astrodome on September 20, 1973. You will cheer and clap as King smacks a volley or hits a winning cross-court shot, and groan when she double faults or hits the ball into the net. Savor her victory: the best-qualified player, an outspoken feminist, trounces an older, out-of-shape male chauvinist pig on the other side of the net.

If only the 2016 election had turned out so well.

“The Battle of the Sexes” puts its politics — both feminist and sexual — front and center, which is rather remarkable for a mainstream Hollywood offering. King takes on the male tennis establishment, personified by unctuous tennis promoter and former champion Jack Kramer (Bill Pullman), and coolly faces it down. As a not insignificant aside, note how Emma Stone stares unblinkingly through wire-rimmed glasses — popularized by feminists like herself and Gloria Steinem — to establish King’s take no prisoners persona: talk about a penetrating female gaze. The other heavy is Australian champion Margaret Court, known then and ever since for her strident anti-homosexuality views, and whose 6-2, 6-1 loss to Riggs on May 15, 1973, the so-called “Mother’s Day Massacre,” set up the Battle of the Sexes on September 20.

But King is not the only feminist hero of the piece. Kramer and Court are also no match for Gladys Heldman, the chain-smoking director of the Virginia Slims tour (played wonderfully by comedian Sarah Silverman) and King’s outspoken doubles partner Rosie Casals (Natalie Morales), who gleefully takes on commentator Howard Cosell during the prime-time television broadcast of the match.

But the film also puts a character on center stage, a woman who was in the background at the time: Marilyn Barnett. King’s feminism was well known in 1973 but her struggles over her sexuality were not, except to a small circle of tennis insiders. During all the hoopla leading up to the Battle of the Sexes, she was having an affair (not her first) with Barnett, a hairdresser-turned-private secretary, despite being very publicly married to former tennis player Larry King.

One of the most challenging tasks for the screenplay was to integrate these parallel, intimate stories with the movie’s real focus: a tennis exhibition, begun as a money making stunt by Riggs, that quickly degenerated into a circus-like atmosphere. “Battle of the Sexes” delivers the first-ever on-screen Billie Jean King sex scene, although the hotel bedroom scenes between the lovers (tennis players spend a lot of time in hotel rooms) are much less erotic than an amazingly sensual blow-out that Marilyn Barnett gives King at the start of their affair.

The need for secrecy about lesbianism in women’s sports is part of the script from the beginning. Knowing the pressure King was under, not just to beat Bobby Riggs but also to conceal an affair she feared would have irrevocably damaged women’s professional tennis, makes audiences realize how much more was at stake in 1973 than just a tennis match. Yet it’s a glass closet from the get-go: Margaret Court, shouldering her newborn baby, reads the situation correctly right away. In response to her husband’s protest that King is married, Court responds sourly that “they are all married.”

Hollywood movies like happy endings and the feel-good nature of this one is linked not just to King’s 6-4, 6-3, 6-3 trashing of Bobby Riggs, but also to an implied narrative arc about gay liberation. To tell this story, the writers use the character of Ted Tinling, who designed the dazzling tennis dresses so lovingly recreated in the film. Tinling’s homosexuality was an open secret in the tennis and fashion worlds, which means his character (played perfectly by Alan Cumming) can speak truth to power. “Be careful,” he warns King, when her growing infatuation with Barnett becomes all too clear to those on the tour. He doesn’t need to name what she should be careful about. At movie’s end Tinling is also given the special responsibility of looking to the future and anticipating breakthroughs that are barely on the horizon in 1973. As he congratulates King on her victory, he commiserates that she has to hide her personal life and predicts that the victory over Riggs is one small battle in that struggle. Times change, he says, and someday we will all be free to love who we choose.

And yet as the film wraps, directors Jonathan Dayton and Valerie Farris present a highly selective coda of what has happened to the main characters since 1973. Billie Jean King is identified – rightly — as a major activist for women’s sports, Title IX and LGBTQ rights. The tribute is accompanied by a shout-out to her longtime partner, Ilana Kloss. We are told Larry King remarried and that Billie Jean and Ilana are the godparents of his children. Bobby Riggs, whose marriage was damaged by his gambling, reconciled with his wife, and they remained together until his death from prostate cancer in 1995.

But there is no information about what happened to Marilyn Barnett.

This is an understandable omission for a Hollywood film, but a glaring one that disrupts the progress narrative about gender and sexuality that “Battle of the Sexes” promotes. How inconvenient it would have been to mention that in 1981, when the two had separated, Marilyn Barnett sued Billie Jean King for “palimony”, asking for a share of King’s professional earnings for the years they had been together. These revelations forced King out of the closet at a brutal pace, making her one of the very first celebrities to be “outed.” With Larry still loyally at her side (they did not divorce until 1987), King told the press the affair had been a mistake (the movie convincingly demolishes this claim), and that there was no merit to Barnett’s claim that she had supported her lover’s career.

The courts agreed, although in retrospect Barnett was a pioneer in asking that same-sex relationships be given the same standing in courts of law as relationships between men and women. Although she was already in a relationship with Ilana Kloss, Billie Jean King basically went back into the closet until the late 1990s, when she finally began to embrace a public role as not just a feminist, but a gay rights trailblazer as well.

The portrayal of Larry King by Austin Stowall is also incomplete. Larry’s role in the film is basically “to know, but not to know,” as Ted Tinling puts it delicately. Larry senses his wife’s conflicted feelings, but never challenges her or pushes back. It all seems a bit too pat. An unexplored reason why Larry was so understanding about, and tolerant of, the affair was that he was deeply invested — professionally and financially — in Billie Jean’s career. In my book, Game, Set, Match, what I call “Billie Jean King, Inc.” provided his livelihood. He promoted tennis tournaments, rounded up endorsements, helped found World Team Tennis in 1973, and then, oblivious to the obvious conflict of interest, owned several league franchises while serving as its CEO. In other words, he had plenty of reasons to participate in the charade of a King marriage that kept the stigma of lesbianism in women’s tennis at bay.

That this is a story the film chooses not to tell does not dim the significance of a tennis match that had real consequences for popular feminism. Those of us old enough to remember watching the Battle of the Sexes will never forget how high the stakes seemed at the time — Billie Jean King, carrying the expectations of half the population on her shoulders, turned a tennis match into a referendum on gender equity as well as athletic ability.

Will these stakes be apparent to viewers just learning about the match for the first time? I fear not. Despite the movie’s full frontal feminism, the take-away point is really about popular culture and entertainment, maybe about tennis, and less so about the political and social controversies roiling the country. But the overall message is just as timely now as it was in 1973; perhaps more so now that the showmanship that Riggs prided himself on has moved, in a more sinister way, to the White House.

Billie Jean King’s decision to play Bobby Riggs was a conscious political act. She always realized that the match was much bigger than tennis, and she was willing to put her hard-won credibility on the line to prove that women deserved just as much respect, and as big a paycheck, as men. If she had lost (not that she ever admitted that possibility) it would have been an embarrassing, indeed humiliating, affirmation of many of the old stereotypes that women at the time were trying to upend. That made her victory, broadcast to a national television audience of 48 million American, even more satisfying. In 1973, future sportswriter Christine Brennan, then a fifteen-year-old aspiring athlete, captured the sweet vindication: “We won. The girls won.”

That’s how I felt when I left the movie theater.

Susan Ware is the general editor of American National Biography and Honorary Women’s Suffrage Centennial Historian at the Schlesinger Library, Harvard University. She is the author of Game, Set, Match: Billie Jean King and the Revolution in Women’s Sports (University of North Carolina Press, 2011)