There have reportedly been audience walk-outs at screenings of this indie drama from young American film-maker Elliot Tuttle, a two-hander about a sex worker hired for the night by his former English teacher, a convicted paedophile. In interviews Tuttle has said his film was rejected by several major festivals. What makes it so uncomfortable is not the sex; mostly what we see on screen is two men talking. But early on a mood of skin-crawling unease seeps in, and it remains for every second of the film’s 82-minute run time.

Kieron Moore plays Aaron Eagle (not his real name), a Los Angeles sex worker and camboy. In the video content he livestreams, Aaron is a dom; gym-perfected and tattooed, he hurls homophobic insults at his fans. One night, he arranges to meet a client who offers to pay $50,000 for one night. The retirement-age man who answers the door of the Airbnb turns out to be Aaron’s former English teacher Mr Grant (Reed Birney), who was sacked after attempting to rape a 12-year-old pupil. Aaron was not the victim, but the teacher says he has always been in love with Aaron – though he is no longer sexually attracted to him.

It’s a film about the stories we tell about ourselves, re-remembering narratives to fit who think we are. Grant does have flickers of self-awareness. But he’s also monstrously self-justifying, pompously telling Aaron that his paedophilia would have been accepted in ancient Rome. The script’s attempts to empathise with his character felt a little simplistic to me, but Birney’s performance is horribly convincing, and Moore is also very good as Aaron, vulnerable under the swagger. It’s a difficult watch: at times feeling like the emotional equivalent of watching these people getting their skin peeled off, layer by layer.

• Blue Film is in UK and Irish cinemas from 11 September.