In 1969, 100 million people tuned in live to Miss World — “more viewers than for the moon landings or the World Cup final,” we learn in a trailer for “Misbehaviour.” Philippa Lowthorpe’s upcoming dramedy depicts the events of the historic 1970 Miss World competition, which was disrupted by women’s rights activists eager to broadcast their agenda to millions of viewers watching from home.

As the spot reveals, the Miss World pageant has been coming under fire for sexism, which is essentially its bread and butter. But its organizers are adamant that the women are not just evaluated for their looks. “We really believe beauty isn’t just skin deep,” administrator Julia Morley (Keeley Hawes) explains. “The girls also get marks on charm, grace, deportment…” “Swimsuits,” her male counterpart adds.

Sally Alexander (Keira Knightley) and other Women’s Liberation members decide they’ve had enough of Miss World and the message it sends about women’s value. They plan to protest the event and call out host Bob Hope (Greg Kinnear) for his misogynist antics. Along the way, they cross paths with the first Miss Grenada, Jennifer Hosten (Gugu Mbatha-Raw), who has altruistic motives for competing.

“If I win, there will be little girls who might start to believe they have a place in the world,” Jennifer says, implying that she could be a role model for black girls. Sally, meanwhile, is afraid that Miss World will teach little girls that beauty is the only thing that will give them worth. “This competition makes us compete with each other, and makes the world narrower for all of us in the end,” Sally declares. “Why should any woman have to earn her place in the world by looking a particular way?”

Lowthorpe directed “Misbehaviour” from a script by Gaby Chiappe and Rebecca Frayn. Lesley Manville (“Harlots”) and Jessie Buckley (“Wild Rose”) also star.

“Swallows and Amazons,” “The Crown,” and “Call the Midwife,” are among Lowthorpe’s other credits.

Knightley’s more recent work includes “Official Secrets,” “The Aftermath,” and “Colette.” You can catch Mbatha-Raw in Apple TV+’s flagship series, “The Morning Show.” She also stars in Brenda Chapman’s “Come Away,” a prequel to the stories of “Alice in Wonderland” and “Peter Pan” that’s set to premiere next month at Sundance.

“Misbehaviour” opens in the UK March 13. No word on a U.S. release yet.