In most movies and TV shows, sex scenes aren't real.
While they often look pretty convincing, the realistic nature is often down to top-notch acting and the work of the crew, including intimacy coordinators who are often used on set.
However, there are some movies in which the sex scenes are 'unsimulated' which essentially means that sex is actually happening instead of the actors pretending.
Advert
Although rare, there are a number of films with unsimulated sex scenes - and some big name actors who've been involved in them, too.
You might have even watched these movies and not actually realised that the scenes were real.
Robert Pattinson
Advert
While he's known more these days for being a sparkly vampire and Batman, back in 2008 he was playing Spanish artist Salvador Dali in Little Ashes.
One particular scene has Pattinson pleasuring himself for real on camera as he believed that faking such things 'doesn't work' as far as authenticity goes.
Speaking to Interview magazine in Germany, he revealed: "My orgasm face is recorded for eternity."
Aubrey Plaza
She appeared in the film The To Do List, and in an appearance on Conan said that when she got to the bit in the script where it said 'Brandy masturbates' the director told her to do just that.
Advert
"In my head, I envisioned a nice scene where you just see my hand slowly go out of frame," Plaza said of shooting the scene.
"I thought I was doing one thing and when I showed up it was a whole different thing, it was a full body shot and I asked the director 'what should I do' and she said 'masturbate like it says in the script'."
Willem Dafoe and Charlotte Gainsbourg('s body doubles)
Advert
If you've seen the 2009 movie Antichrist, then you'd be forgiven for thinking that you actually saw leading actors Dafoe and Gainsbourg having sex.
While unsimulated sex goes on in the film, the bits you can't fake were performed by body doubles.
According to director Lars von Trier, Dafoe was 'too well endowed' and his enormous thingamajig would leave audiences 'confused'.
The actor was later asked about this himself and said that the real reason they had doubles for the unsimulated sex scenes was that 'Charlotte and I are both married and I’m not sure everybody would be cool with that'.
Chloë Sevigny and Vincent Gallo
Advert
Directed, written and produced by Vincent Gallo, he also starred in one of the leading roles in The Brown Bunny.
Starring alongside him was Chloë Sevigny, who in the movie performed unsimulated oral sex on Gallo.
Sevigny spoke further about the film in an interview in 2010, saying 'what's happened with that is all very complicated'.
She said: "There are a lot of emotions. I'll probably have to go to therapy at some point. But I love Vincent. The film is tragic and beautiful, and I'm proud of it and my performance.
"I'm sad that people think one way of the movie, but what can you do? I've done many explicit sex scenes, but I'm not that interested in doing any more.
"I'm more self-aware now and wouldn't be able to be as free, so why even do it?"
Kieran O'Brien and Margo Stilley
9 Songs is a movie where the leading actors have unsimulated sex multiple times on camera, with O'Brien having to wear a condom in the scenes to avoid the risk of pregnancy.
Obviously this was quite a controversial movie, but Stilley has said she doesn't regret having done it.
She once told the Irish Independent: "It was a film about love and sex. It wasn't porn. I mean, I had sex with my boyfriend last night and that wasn't porn. It was just hot sex!
"9 Songs was a real film about love and sex, and I wanted to do that film and I am proud of it."
Lauren Lee Smith
Her first reaction when her agent told her that her part in Lie with Me would require not just nudity but also live sex on camera was to ask: "Are you kidding?"
As part of her audition she had a chemistry test with co-star Eric Balfour, and 'there was apparently chemistry'.
Kerry Fox and Mark Rylance
The 2001 film Intimacy took the title quite literally, and in the movie, Rylance plays a bartender who ends up in a casual relationship with a mysterious woman played by Fox.
In the flick there was an unsimulated oral sex act, and Rylance said the film was the 'most difficult job' he took in large part due to that scene.
He said: "I was convinced it was a vital story about the difficulties people face finding intimacy in a big city like London.
"Hanif Kureishi's writing couldn't have been more intimate and revealing, but I found the making of the film and the subsequent publicity and personal attacks very, very painful. I wish I hadn't made it."
He said he felt 'undue pressure' from director Patrice Chéreau to do the scene and thought that at the time he lacked the confidence to say no.
For her part, Fox said doing the film was 'not one of her regrets'.
Not the headline cast of Nymphomaniac
While Shia LaBeouf said Nymphomaniac basically had a disclaimer 'that basically says we're doing it for real', the movie actually took a different approach.
Movie producer Louise Vesth told The Hollywood Reporter that the body doubles actually had sex and digitally imposed that over the actors.
She said: "We shot the actors pretending to have sex and then had the body doubles, who really did have sex, and in post (production) we will digital-impose the two.
"So above the waist it will be the star and then below the waist it will be the doubles."
Topics: Celebrity, TV and Film, Sex and Relationships
Lucy Devine