Sometimes, societal change comes in the aftermath of powerful street protests. Other times, it comes accompanied by horns, dancers and outrageous costumes in a spectacle worthy of an end-of-times bonanza.

We get a glimpse of the latter proceedings in Battle of the Sexes, a movie about the simultaneously real and surreal 1973 matchup between tennis Hall of Famers Billie Jean King and Bobby Riggs, starring Emma Stone and Steve Carell in period-appropriate hairdos and athletic ensembles.

The film takes us back to a not-too-long ago dark age, when women still needed a man's signature to apply for a credit card. The then-recent passage of Title IX promised to create new opportunities for female college athletes, but women's sports were still generally treated as a novelty. It was largely through the efforts of King, who spearheaded the formation of a new tour and threatened to boycott tournaments, that the pay gap began closing between her colleagues and those on the men's side. 

Enter Riggs. A champion from the World War II era, Riggs derived little satisfaction from his subsequent office job, preferring to hustle opponents on the golf course and in the poker room. A return to the men's senior tour scratched some of his competitive itches, but what he really craved was the spotlight and a megaphone.

By early 1973, the 55-year-old Riggs was garnering some badly needed attention by slamming the quality of women's tennis and demanding to face its top players. He was generally ignored by his targets, but that spring he found a taker in Australian champion Margaret Court.

Court, then 30, was in the midst of a career that produced more Grand Slam singles titles than any other player – man or woman – in history, but she was ill prepared for her May 13 matchup with Riggs. Thrown off by the hustler's assortment of lobs, drop shots and other tricks, Court quickly unraveled en route to a 6-2, 6-1 rout that was dubbed the "Mother's Day Massacre."

Flush in victory, Riggs immediately called out the opponent he preferred all along: "Now I want King bad," he announced. "I'll play her on clay, grass, wood, cement, marble or roller skates . . . We got to keep this sex thing going. I'm a woman specialist now." King already had plenty on her plate, including, as it turned out, a secret relationship with her female assistant, but she knew there was no choice if she hoped to maintain the hard-earned gains for women's side. That July, the 29-year-old formally agreed to a $100,000, winner-take-all match with the sport's reigning loudmouth.

Following a summer of campy trash talk (Riggs: “I’ll tell you why I’ll win. She’s a woman and they don’t have the emotional stability.”), the "Battle of the Sexes" was ready for prime time. On September 20, 1973, more than 30,000 fans filed into the Houston Astrodome – itself something of a novelty, as one of the new indoor arenas that would become part of the American sporting landscape – with celebrities like Salvador Dalí mingling with what appeared to be aliens wearing tuxedos.

Embracing the spectacle, King entered the playing court on a gold litter carried by four shirtless members of the Rice University track team, while Riggs arrived via rickshaw, flocked by his bevy of "Bobby's bosom buddies." They then exchanged pregame gifts: A baby pig for the chauvinist Riggs, a giant Sugar Daddy lollipop for King.

While the carnival-like atmosphere continued in the stands, King got down to business on the court. After falling behind early, she broke Riggs's serve to pull even, and then continued her onslaught from the baseline. Riggs, meanwhile, realized he would have to work harder than intended, and shed his Sugar Daddy jacket after three games. Furthermore, his usual grab bag of tricks was yielding nothing of substance, and he uncharacteristically double-faulted to hand the first set to his opponent.

It was more of the same in the second and third sets, with King wearing out the older Riggs in key points as her supporters celebrated in the stands. The outcome, while not as one-sided as the Mother's Day Massacre, was nevertheless decisive in its own right, as King swept to a 6–4, 6–3, 6–3 victory. Riggs demanded a rematch (which he never received) but was also unusually humble in defeat, conceding that he had underestimated King's abilities.

Billie Jean King

Billie Jean King holds her trophy high after beating Bobby Riggs in their $100,000 winner-take-all 'Battle of the Sexes' tennis match.

Decades later, the match remains a cultural touchstone as both a symbol of the anything-goes '70s and a measuring stick for progress. That year, the U.S. Open became the first of the four Grand Slams to award equal prize money to its men's and women's champions, an act that was finally matched by the lone holdout, Wimbledon, in 2007. Meanwhile, the clear successes of King and her colleagues paved the path for women across an array of sports to become household names, from Jackie Joyner-Kersee to Danica Patrick to Ronda Rousey

Which isn't to say that an old-fashioned perception of the value of women’s sports has faded. In 2016, Raymond Moore of the Indian Wells Tennis Garden, host of a prominent annual tournament, quipped that the members of the women's tour "ride on the coattails of the men.” More recently, former tennis bad boy-turned-analyst John McEnroe felt the need to point out that Serena Williams, arguably the greatest women's player ever, would be ranked "like 700 in the world" if she played against the guys.

That may or may not be true, but, as Stone has noted, it’s entirely beside the point.

“Billie Jean’s argument, and the argument that’s in the movie, was never that female tennis players are better than the men,” she said. “It was that we get butts in seats equally . . . If someone is doing the same job they deserve the same pay."

In an era of big-money sports, in which the dollar drives the decision-making, that may be the point that ensures that King’s efforts, highlighted by an outsize exhibition 44 years ago, will ultimately stand the test of time.