At 16, Martin (De Pietro) is handsome and he knows it. But one evening after swimming practice, he's left without a place to stay, so ends up hanging out with his teacher Sebastian (Echevarria). Sebastian worries about the ethics of having an underage teen in his flat all night, and his girlfriend (Costa) won't come round. But what he should be worried about is Martin's clear obsession with him. The next day, Sebastian discovers that Martin had lied about being locked out the night before. And the tension between them only grows from there.

Berger is a filmmaker who says more with a tiny glance than with a page of dialog, and he immediately gets us into Martin's perspective. We know just where Martin's interests lie, as he watches his fellow students in the locker-room, then takes note of his own handsome face in the mirror. This provides the slow-burning intensity of a horror film as the understated dialog and gentle pacing are layered with glimpses of other things going on under the surface.

Even so, De Pietro plays Martin as a typically absent-minded kid, even as he knows exactly what he's doing. Berger's camera is often uncomfortably close to him, lingering over his physique to suggest the way everyone stares at him. And his casual physicality is seductive, especially as he begins to prowl around Sebastian. Opposite him, Echevarria brings a realistically layered sense of confusion, as Sebastian clearly has no idea how to deal with or even react to the situation.

This vague approach sometimes leaves the film without an urgent sense of momentum (indeed, the story screeches to a stop at one point). But there is a gurgling intensity that holds our interest, playing on the fantasy elements in the premise to taunt us with what might happen next. And a turn of events in the final act sends the film in a surprising new direction that is impossible to predict: internalised, thoughtful and haunting.

Anna (Rapace) moves into a new flat with her 8-year-old son Anders (Werring). Fleeing her abusive ex, she is consumed with paranoia that Anders isn't safe. Her social workers (Amdam and Bock) force her to put him back in school. While she waits for him every day, she quietly befriends Helge (Joner), a nice guy who works in an electronics shop where she buys a Babycall monitor to keep an ear on Anders. But while listening one night she overhears what sounds like another child being violently abused and maybe killed.

As the story progresses, it becomes increasingly clear that Anna's mind is slipping. People and places don't quite stay in the proper space and time. Is she psychic? Is she traumatised from her past experiences? Or is she just crazy? Indeed, Anders seems a bit wary of her. And Helge also begins to have doubts, especially when he meets a strange boy (Hoeg) who passes himself off as Anders.

There are serious problems with the way writer-director Sletaune shifts perspective from Anna to Helge, since this feels like a cheat to the audience. Sure, Anna might not be seeing events quite the way they really are, but when we witness a scene through Helge's eyes, it shouldn't be unreliable, right? But Sletaune has no qualms about violating our trust, which makes the final act more than a little frustrating.

That said, Rapace is terrific as a woman so dazed by what has happened that she forgets to even run a comb through her hair. The way she clings to Anders draws us into her worldview even as we begin to suspect that she perhaps is seeing something either imaginary or supernatural. And Werring is terrific as the gentle nerd who can't quite believe his luck at meeting such a gorgeous woman and thinks maybe he can help her get through this nightmare. These superb performances, and Sletaune's unblinking filmmaking style, at least mean that the final scenes pack a powerful punch.

Julio (Noguera) applies to type up the handwritten manuscript of noted novelist Gazmuri (Medina). He didn't get the job, so he instead starts writing his own novel, drawing inspiration from his relationship with Emilia (Galgani) eight years earlier. But the writing is going slowly, and he hasn't confessed to his neighbour-girlfriend Blanca (Gonzalez) that it's really his own work rather than Gazmuri's. Then an old friend (Arancibia) tells him that Emilia is back in town.

The title refers to a plant in the novel, which represents its central relationship. Writer-director Jimenez tells the story through extended flashbacks, loading the film with literary references and witty sight gags that almost make it feel like a silent movie. Indeed, Noguera plays Julio as a hapless, Chaplinesque figure who says more with deadpan expressions than he does with words. Meanwhile, Gonzalez's Blanca is both curious and aloof, while Galgani's Emilia is an edgy rock chick.

With such disparate characters, much of the the dialog is random and meandering. And relationships with Blanca and Emilia never really develop into anything hugely meaningful to Julio, who remains a solitary figure even in their presence. This makes it somewhat difficult to understand their attraction to him, beyond his artistic soulfulness. But it also makes Julio more appealing as the protagonist of this story, as we long for him to break out of his stunted fling with Blanca and finally start growing up.

The film is shot and edited with skill, even if the slacker-style pacing sometimes stretches our patience and interest. The images are lush and sensual, focussing on the characters in a way that shows us their personalities between the lines of an oblique script that's infused with asides about reading and writing. But Jimenez beautifully captures the emptiness of a convenient relationship that probably never should have started as well as the yearning for a past romance that seems to have been perfect, even if it wasn't.

Gabriel (Fjalarsson) is a serious student trying to figure out who he is. On a school trip to England, he meets Marcus (Stefansson), an attractive party-boy who opens his eyes to having a bit more fun in life. And as they bond, Gabriel finds confidence to examine his sexuality. Back in Iceland, this changes the way Gabriel reacts to the issues his friends Stella (Gardarsdottir) and Greta (Eiriksdottir) face. So while they hang out with friends, drinking and talking about sex, their yearnings and heartbreak continually gurgle under the surface.

Director Z (short for Zophoniasson) uses a gently realistic filmmaking style, creating likeable characters by coaxing low-key performances from the young cast. On the other hand, all of the adults in the film are panicking, invasive, nagging and useless, from Gabriel's nosey mother to Stella's vile control-freak grandmother. This may have been done in an effort to capture the young characters' perspective, but it sacrifices authenticity as a result.

That said, the intertwining strands of relationships between the teens are intriguing. As they grapple with alcohol and sexuality, they also discover that they need to take a responsibility for each other. And they are also exploring themselves, determining how they will live their lives and with whom. The cast members give the film an edgy urgency even if the plot never quite seems to get up to full speed.

All of this is nicely shot in an intimate style that helps paper over the more overwrought melodramatic scenes. And at the centre of this group of young people, Gabriel's personal journey is thoughtful and meaningful, especially as he struggles to accept his own sexuality even as he gets involved in what his friends are going through. So when the final scenes play out, they feel both provocative and emotionally resonant. And also strangely satisfying for this kind of film.