First up, an actor (Kjeldsen) talks about a director making a move on him: "I have a girlfriend, but this could make or break my career." Then a couple (Graham and Knowles) hosts an awkward dinner for their sons, one of whom comes out as a puppet. A coke-snorting 16-year-old (Hoffman) is ready to make some money, whatever it takes. A guy (Bradberry) remembers meeting someone in the street, having sex, feeling romantic. A man (Twardokus) taunts an old classmate before turning violent. A boyfriend (Stickles) riffs reasons why his partner wants to breakg up. A man (Cusimano) gets a lecture from his reflection in a variety of personas. And in a 1982 hospital room, a dying patient (Wakeford) tells his story to a journalist.

Most of these feature guys speaking to-camera in ways that are overwritten and overplayed rather than spoken off-the-cuff. Along the way, there's some raw emotion and a sense of lingering darkness, plus a few intriguing twists (and one very nasty one). The clips are punctuated by audio bytes and on-screen text, and the technical quality is mixed. Vox's sex club beat-poetry rant looks like it should be dark and interesting, but his words are obliterated by an oppressive sound mix.

The actors do what they can in this heightened atmosphere, but the monologs are so stylised and pessimistic that most are difficult to engage with. One segment is simply Goss singing a grim, emotional song with his guitar. Thankfully, the topics are very strong, never turning preachy even when they touch on some big, thoughtful issues. There are also some refreshingly funny bits, as well as resonant observations, although never too deep.

But there's something in here everyone can identify with. Abandoning artistic ambition to pay the bills? Reluctantly admitting a fetish? Holding on to a crush? Themes range from coming out and Aids to fantasies and manscaping. While each segment is about sex, it's only verbally so. On-screen interaction is realistic, but the camerawork is coy. So it's a film about sex that's only rarely sexy. So in the end, it's provocative and challenging, but never quite goes anywhere.

With his dad (Rashed) in hospital, Salah (Abaza) steps up to run the family kebab shop, promising that he won't let his university studies slip. But the customers are a succession of out-of-control young drunks. As Saleh struggles to cope, an accident pushes him over the edge, and he starts making kebabs out of his most abusive customers. Making things worse, the chief offenders are revellers from the nightclub former reality TV star Jason (Williams) has established in the property Salah's dad planned to turn into an upscale restaurant.

A brief prologue establishes a Saw-like undercurrent, while the entire film is punctuated with doc-style clips of wasted young people on stag and hen nights. And as Salah's story unfolds, writer-director Pringle layers blackly comical nastiness with strong underlying emotion. This edgy combination never falters, graphically depicting both the cultural excesses and Salah's extreme reaction. And while the film could use some judicious editing, the suspense is stronger because there's something to it.

For a vigilante serial killer, Abaza is remarkably engaging, a nice guy who can't take any more of the ugliness around him. With the efficiency of Dexter, he's cleaning up the vomit-strewn streets. And the script adds sympathetic detail by dipping into his immigrant past. So it's a bit handy that Williams' sneering charmer Jason is the real monster. Atherton adds depth as a hotel manager who understands why young people need to let off steam, as does Noi as a young guy who asks Salah for a job. And the believable supporting cast of abusive drunks seriously goes for it.

Much in this film is exaggerated for maximum effect, including the protracted conclusion, but Pringle makes it eerily recognisable to anyone who has encountered a drunken Brit. Salah asks the question everyone thinks, "I want to know why you think it's acceptable to behave the way you do?" Or as a cop says, "Of course have a drink, but don't be an idiot." It's rare for a grisly horror movie to deepen characters while astutely tapping into social issues. And it'll definitely make you hesitate before ordering the lamb doner.

In the first segment, a blond twink (Hau) takes a job for another young man (Norman). Both are clearly upset by something, but what the client wants is seriously disturbing. Next there's an angry performance artist (Yang) belting out his punk beat poetry with the help of a deejay (Monnier) while an audience member (Baron-Moreau) tries to connect with him physically. On to a train platform, where a young bald guy (Puyau) meets a shaggy kid (Eiri) who offers sex in exchange for heroin. But their thoughts are on something more important.

This theme echoes in the surreal sequence that follows, in which two anarchists (Hameline and De Alessi) are wearing fur suits and camping in the snow. A passing skater dude (Gabriel) falls into their clutches, and they're not sure whether to kill or rape him. Finally, on a beach strewn with concrete ruins, a lonely man (Rameau) strolls around, entering a bunker watched on-camera by a woman (Vienne) in a control room. She wants to help him, but he feels like a drain on the world.

All of these clips are raw and earthy, and also bleak and sad. The ethnically eclectic actors give understated performances that add to the film's overall muted, stunned tone (they're even impassive in sexual situations). Farley shoots this intriguingly, challenging the viewer by lingering in unexpected places, cropping people out of frames and generally forcing the audience to look closely.

Most of these scenes are also wordless, which suits a cast made up mainly of models. They convey the profound feelings that each character is dealing with, usually in an unhelpful way. Is this about the inexorable approach of death? The yearning difficulty of finding companionship in a sex-obsessed culture? Whatever, the themes resonate in the relationships and some lusty interaction. And through it all, it's impossible not to feel the powerful need we all have to be loved.

In Brooklyn, Naz and Maalik (Johnson and Cook) are teens with a number of secrets. First-generation Americans, they're openly muslim and privately gay. Lively fast-talkers who sell things on the streets and in the Subway to raise money for college, they attract the attention of two FBI agents (Grier and Custer) who are investigating potential terror threats. But the bigger problem is that Naz's sister Cala (Awusie) has spotted them kissing each other.

Johnson and Cook are cheeky and engaging. Full of youthful energy, the chemistry between them is riveting, which allows the film to reveal their relationship at a gently authentic pace. Their interaction is a terrific mix of playful teasing, lust, affection and intriguing shades of darker emotions. Refreshingly adding context to the film, the surrounding characters have a nice sense of their own lives while offering astute textures to Naz and Maalik's story.

The film is shot in a realistic, almost documentary style that captures the rhythms on the streets and the colourful characters even when the quietly gurgling plot threads threaten to take over. There are two threats against these guys: the danger of getting entangled with the FBI and the risk of their families discovering their sexuality. And the depiction of teens grappling with both of these things feels earthy and authentic.

Sometimes the plot seems to slip out of the filmmaker's grip, with continuity and logic problems, but the central relationship is solid. This is an astute film that takes on serious issues without ever giving into the drama of them. Scenes remain bracingly down to earth, with sparky dialog and a sense that the relationship is the most important thing here, rather than the religious or political issues that hang over the characters' heads.