A government advert is being launched to try to get teenagers to think about where the line is between consensual sex and rape.
It is to be shown after warnings that many teenagers don't think it counts as assault if it happens in a relationship and that it only involves strangers.
The ads will run for a month online, at cinemas and during youth-focused TV shows like E4's Skins.
In the adverts, a couple are seen in a bedroom as a party goes on downstairs.
The boy wants to take things further.
The girl says, 'I don't want to' but he carries on anyway.
The mood changes and a double of the boy appears, watching in horror from behind an invisible barrier.
"He's got his mind on one thing," says actor Sam Gittins, 18.
"He's not thinking about her feelings, or her consent, or anything like that."
Eighteen-year-old Issy Brazier-Jones, who plays the girl, adds: "Girls, teenagers, women - they're either scared, or they don't even know where the line is. Where is it crossed?"
According to official figures, a third of teenage girls and about one in six boys says they've experienced sexual violence from a partner.
About a fifth of 16-to 20-year-olds also thought it was probably acceptable for a boy to have sex with a girl if he had spent time and money on her.
Newsbeat watched the advert for the first time with 19-year-old Tasnim, which is not her real name.
When she was 14 she got into a relationship with someone who would regularly beat her to make her have sex with him.
"They don't listen," she says. "Then they say, 'Oh, I never heard you say no. You never said no. You were OK with it.'"
She first had sex with her boyfriend because she was scared he would leave her if she didn't.
He also said he would spread naked pictures of her if she followed through with a police complaint.
"He used to beat me and rape me when I was unconscious," she says. "What if he did take pictures of me?"
She eventually spoke to professionals, who made her realise for the first time that she was being repeatedly raped.
Her story is too graphic to go into in more detail but it is what this new advert is intended to tackle.
Equalities Minister Lynne Featherstone said it "aims to dispel the myths that can lead to acceptance of rape in relationships".
Victims' workers say it is a start but say too many men accused of rape go free and that abuse services need more funding.
Tasnim adds: "They should go into schools, to teach girls about rape.
"It's OK to be a virgin. It's OK to not have sex with your boyfriend."