“I get letters every day from people around the world, saying, ‘Oh my God, thank you for making this’,” says Nina Menkes. “But one woman told me, ‘You’ve ruined all my favourite films’.”

Menkes is the director of Brainwashed: Sex-Camera-Power, a documentary arguing that even the most acclaimed classics of cinema have encouraged a culture of sexual harassment of women. Using hundreds of clips, Menkes shows how female characters are consistently framed as the object by the male subject.

We see sex scenes full of fragmented female bodies, shown part by part. Women’s behinds being ogled by the leading man. Endless passive, even unconscious objectified women. At the movies, sexualisation doesn’t always stop once you’ve breathed your last.

“I’m dead in bed,” says Rosanna Arquette of her role in Martin Scorsese’s After Hours, “and the camera goes slowly down my body. I look back on that now and go wow, what was I [thinking]? … It was just part of what you did.”

I host a feminist film podcast, and I’m also a fan of Blade Runner – which can be hard to reconcile. There’s a scene in which Harrison Ford aggressively refuses to accept Rachael turning down his advances. She eventually relents, soundtracked by Vangelis’ seductive Love Theme. This is just one of the myriad examples Menkes came across of a lack of consent being brushed off, or even glamourised. Their cumulative influence on “rape culture” is less easy to dismiss.

“Everybody knows that women tend to be objectified in advertisements and music videos,” says Menkes. Less well known is its ubiquity in the canon. “The great directors that everyone reveres. These films that many people consider to be their favourites reinforce a way of seeing women that’s detrimental to our lives.”

Talking heads analyse the effects of such imagery, from academics such as Laura Mulvey to directors including Julie Dash and Catherine Hardwicke. The absence of white, male, heterosexual speakers was accidental, says Menkes. “We were kind of shocked because it was not our plan.”

Menkes does include discussions with a mixed group of film students, one a young man who says he now realises how much movies have trained him to treat women. “It makes us think we can just have whichever one we want.” Major male directors are absent. “We reached out to a lot of the big directors whose clips we included, including Scorsese and Spike Lee,” says Menkes. “Denis Villeneuve, because we use his clips quite a few times. And we got the brush off.‘Busy, sorry’. Without trying, we ended up with a group of people who were very powerfully reinforcing the message.”

Yet Menkes also uses incriminating examples of objectification from films by female directors – from Sofia Coppola’s Lost in Translation to Julia Ducournau’s Titane. “Patriarchy has no gender,” says Menkes. “We’re not saying, if you have a male body, you make this kind of movie. It doesn’t break down like that.”

Menkes took suggestions for films to include from her students. One felt Magic Mike – with audiences encouraged to ogle an oiled-up Channing Tatum et al – was a good reverse example. “So I went back to check it and it supports my thesis. When men are sexualised, they are sexualised completely differently, as subjects.”

Menkes was raised in California, by Jewish parents who had fled Europe as children. “It’s in my family, this idea that power structures can be corrupt,” she says. “You don’t have to bow down to existing laws, as those laws might be corrupt.”

Her mother encouraged Nina to examine her own relationship with gender. “I remember when I was 15 or something, I came home and I was like: ‘Oh, Mom, guess what? David told me that I’m the most wonderful woman in the world and he really likes me!’ And I was all excited. And she said, ‘OK, but do you think he’s the most wonderful man in the world?’ I never forgot that. It was such a shock. It was like: ‘Oh, what do I think?’”

Brainwashed: Sex-Camera-Power is in UK and Irish cinemas on 12 May. Nina Menkes is in conversation at BFI Southbank on 10 May as part of the film season Cinematic Sorceress: The Films of Nina Menkes running 6-31 May.