Review: Misbehaviour (12A). Rating: 6/10
The fight to end female objectification explodes in a cloud of white flour in director Philippa Lowthorpe's timely drama of empowerment and activism.
Based on a true story, Misbehaviour harks back to an era which crudely defined swimsuit-clad physical perfection as a curvy 36-24-36.
Screenwriters Gaby Chiappe and Rebecca Frayn distil emotionally charged newspaper headlines from November 1970 into an entertaining but lightweight rallying cry against sexism, which preaches politely to the Me Too and Time's Up congregations.
Key messaging is divided predominantly between Keira Knightley's prim academic and Jessie Buckley's authority-flouting motormouth, who baits the police by defiling offensive billboard adverts with a can of spray paint.
Fractiousness predictably mellows into sisterly solidarity, building to a climactic act of defiance in front of an estimated 100 million TV viewers - more than the moon landings.
Caught in the middle is Gugu Mbatha-Raw as the first Miss World contestant from Grenada, who intends to use her appearance to convince girls back home that 'they have a place in the world'.
She is luminous as an internally conflicted trailblazer committed to disproving assumptions that beauty is skin deep.
Regrettably, Lowthorpe's film doesn't follow her example and glides elegantly on the surface of characters' clashing ideals.
The first voice for change is historian and working mother Sally Alexander (Knightley), who experiences gender discrimination in her pursuit of academic excellence.
She answers the call of an outspoken wing of the Women's Liberation Movement, whose rabble-rousing members include Jane (Lily Newmark), Jo (Buckley), Sarah (Ruby Bentall) and Sue (Alexa Davies).
'You get the world you deserve and if you don't fight, you deserve the world you get,' flame-haired Jo scolds Sally.
They plan a high-profile protest outside the 1970 Miss World beauty pageant organised by Eric Morley (Rhys Ifans) and wife Julia (Keeley Hawes).
Sally suggests the activists could buy tickets to the show, infiltrate the audience and disrupt the live TV broadcast with flour bombs and football rattles.
The women engineer their audacious plan as comedian Bob Hope (Greg Kinnear) arrives in London to host the pageant, accompanied by his long-suffering wife, Dolores (Lesley Manville).
Meanwhile, Miss Grenada Jennifer Hosten (Mbatha-Raw) nervously prepares to make her island proud against bookies' favourite Miss Sweden Marjorie Johansson (Clara Rosager), Miss United States Sandra Wolsfeld (Suki Waterhouse) and Pearl Jansen (Loreece Harrison), the first black competitor from Apartheid-era South Africa.
Misbehaviour never threatens to embrace the disorderly conduct or minxiness teased by the title.
Lowthorpe's film serenely follows a path of least resistance to shoot at sitting ducks of male chauvinism, represented on screen in broad strokes by Ifans and Kinnear.
Gentle laughs bookmark a crowd-pleasing dramatisation of real-life triumphs, emboldened by resolute performances from an impressive ensemble of homegrown talent.