4 stars

When organisers were getting ready for the Miss World contest in 1970, there were plans afoot to gatecrash the televised event and spoil their party. A group of radical young feminists in another part of London were hatching a plot to disrupt it as the winner was announced with the world media watching.

Misbehaviour, based on true events, is about the main players in the story - the group of radical young women and some of the key contestants, and others too. American comedian Bob Hope who officiated and the British entrepreneur behind it, Eric Morley.

It is delicious to watch the two opposing forces, the organisers and the disrupters, on a collision course during the set-up in the early scenes.

I thought the very versatile Rhys Ifans might have done more with his role as Morley, but thought again. As a recent owner of the sister contest in the US, Miss Universe, Donald Trump has probably already done enough to besmirch the name of men in the beauty business.

The male characters are fascinating, especially the pageant host Bob Hope. Greg Kinnear is outstanding as the very dubious king of comedy, an embodiment of 1970s male chauvinism, a flagrant womaniser who thrived on the opportunities afforded him. But the Misbehaviour story belongs to the women.

To the protesters who got themselves arrested and to the contestants, in particular the bolshie favourite Miss Sweden (Clara Rosager), the winner Miss Grenada (Gugu Mbatha-Raw), and the blow-in, Miss (Black) South Africa (Loreece Harrison).

As Sally Alexander, a single mother and mature-age student at University College London, Keira Knightley has the lead role.

A few early scenes explain her personal journey and convey the tenor of the times, such as the way the interview for a university place is conducted by a panel of male academics, and her experience in tutorials once she gets in. Sexist foibles were not confined to men in show biz.

Serendipity connects Sally with a collective of radical young women who deface and subvert advertising posters. They turn them into feminist messages of protest, when they're not producing their own campaign posters demanding equal rights for women. One of the women is Jo Robinson, played by the terrific Irish actor, Jessie Buckley (Wild Rose, I'm Thinking of Ending Things).

It's Knightley's character, a single mother with a male partner, who supplies the narrative focus and the glue between the world of academia and radical collective that believes that television is an arm of state oppression.

Women's liberation was, of course, one of many activist movements afoot in 1970. The movement against the Vietnam War was huge, and the anti-apartheid movement was big too.

The year, 1970, was pivotal for people of colour in the beauty pageant too. Not only did the Miss World organisers have angry feminists to deal with, they had activist Peter Hain (played here by Luke Thompson) to answer to as well.

There is a small scene in which the white South African anti-apartheid protestor who had spearheaded the anti-apartheid movement collars Morley. He wants to know why there is no black South African contestant at Miss World, to reflect the reality that 80 percent of the country's population is black. Morley quickly sends South Africa a request for a black contestant to stand alongside the white woman already in attendance.

The year that the Miss World contest was besieged by a feminist protests was the year that the first black woman won the contest. It makes for an interesting exchange in the ladies powder room between Knightley's Sally Alexander and Mbatha-Raw's Miss Grenada, a dignified Jennifer Hosten.

At the film's conclusion, the filmmakers include present-day cameos of Hosten and other key characters. It's good to see that the experiences in 1970 did no one any professional or personal harm.

Misbehaviour is an all-girl show, in front of the camera and behind it. And it's a really good story that makes its points with sharp writing, spirited performances and a light touch.