On a dating website, mortuary attendant Gloria (Duenas) is matched with Michel (Lucas). Leaving her daughter with a friend (Bissot), Gloria agrees to a date. And she succumbs to his charms. Even after she discovers that he regularly woos women for cash, she offers to help. Posing as brother and sister, he seduces two rich widows (Le Merdy and Loop), but Gloria's jealous rage turns fatal. Finally, Michel decides that if he wants to have his way with the young widow Solange (Noguerra) he'll need to sedate Gloria. As if that will stop her.

Cleverly, Du Welz frames this as a love story between two people who define their relationship in fiercely unconventional terms. As they con these wealthy women together, both fight against society's restraints: Gloria wants Michel to remain faithful, but he can't resist temptation. This warped relationship springs to life in the hands of Duenas and Lucas, who unflinchingly reveal their characters' souls, exploring the twisted desires that hold them together.

This complexity makes the characters eerily sympathetic, which adds to the horror of each nasty scenario. As it becomes clear that this pattern of romance and jealousy will repeat, Du Welz merrily cranks up the suspense, then pays off each sequence with a blast of astonishing grisliness, after which Gloria and Lucas are left to (ahem) lick their wounds, patch up their relationship and move on to the next target. In other words, this is a wonderfully subversive romance, exploring the toxicity of standard roles through an extreme lens.

Speaking of which, Manual Dacosse's cinematography is gorgeous, adding a grainy texture to carefully framed shots that centre on emotional reactions rather than physical actions. It's a look and tone that's remarkably original for a horror movie, and it allows Du Welz and his cast to shock the audience repeatedly even as we're confused by our messy emotional reactions. These people may look and behave like monsters, but they're just searching for love like the rest of us.

The gist of it is that the young dancer Octavio (Ramirez) is on a month's break due to an injury just as he enters a relationship with photographer Emiliano (Hugo Catalan), who is making a film about his dance company. But Emiliano constantly flirts with other dancers and prostitutes. When Octavio catches him with another man, he loses the will to live. But his female dancing partners try to cheer him up, and get him dancing again. Meanwhile, Emiliano shacks up with sexy escort Jazen (von Sternenfels), but pines after Octavio.

While the film has a heightened sensual tone that's mesmerising, Hernandez's approach is wilfully obtuse. Is an interlude featuring an existential encounter between two men and a woman supposed to symbolise something? Or is this a choreographed scene from Emiliano's film? Perhaps it doesn't really matter, as Hernandez keeps all of his characters in a constant state of arousal, flirting and touching, but only truly communicating through tiny glances.

Scenes are beautifully staged with a pungent physicality, but this feels so superficial that the film seems to be more about how it looks than what it means. Perhaps Hernandez wants to make a connection between the struggle for romantic permanence and artistic creation. Can an artist never be happy, either in a relationship or with what he's created? Or maybe Emiliano just prefers watching sex to taking part, because love is elusive.

Through all of this, the actors give natural, loose performances, even if their facial expressions feel choreographed and voiceover monologs are like not particularly expressive poetry. The skilfully staged physical encounters offer tantalising possibilities that remain out of reach. Hernandez seems to want this to be a Lynch-style fever dream within a dream, but while the imagery is gorgeous and often very sexy it never generates much of an emotional response. So it feels like something that should be playing in an art museum, not a cinema.

Returning to work following an emotional breakdown, Sandra (Cotillard) is stunned when her colleagues vote for €1,000 bonuses, meaning that she's laid off. Her friend Juliette (Salee) helps push the boss (Sornin) to run a re-vote Monday morning by secret ballot. Now Sandra has the weekend to convince coworkers to sacrifice their bonuses so she can keep her job. Her husband Manu (Rongione) accompanies her in this degrading, desperate task, and has to keep reminding her that she's up for it. Each victory gives her a boost, but not everyone is willing to save her.

The Dardennes base the film on a real scenario, and never question it. They just tell the story in a fluid, involving way that carries the audience on this difficult journey with Sandra. And the mind boggles: how can workers be given a choice between cash or depriving their most vulnerable colleague of the ability to support their family, simply because the company owners want to save a bit of money?

Cotillard is superb, investing real humanity into this woman who hates begging her friends to keep her off the dole. At every step she's clearly overwhelmed but pushes through, hiding emotions from her husband, kids and everyone else. Each person she confronts has his or her own needs and fears, adding layers of complexity to the charged interaction. Some coworkers are compassionate and reasonable, others are ice-cold. But all of them are strikingly realistic.

As usual, the Dardennes let the plot unfold almost imperceptibly as Sandra goes through cycles of joy and despair with quiet resignation. She knows she has a loving family and colleagues on her side, yet being put in this position is unbearable. In the end, we long to believe that human decency will win the day, but the Dardennes have a remarkably clever final kick that says a lot more than the audience expects. This is riveting, provocative, essential cinema.

In 1960 Patagonia, Eva and Enzo (Oreiro and Peretti) are preparing to drive to their new home with their three children: teen Tomas (Daicz), under-developed 12-year-old Lilith (Bado) and youngster Polo (Marselle). They agree to travel with German doctor Helmut (Brendemuhl), who takes an interest in helping Lilith grow to a more normal size. When Eva and Enzo open up their vast lakeside hotel, Helmut becomes their first permanent guest. He also takes an interest in Enzo's doll-making sideline, and is more than a little to excited to discover that Eva is expecting twins.

The title refers to Lilith's handmade doll, which filmmaker Puenzo positions as a symbol of Helmut's interest in children. And since the story is told from Lilith's point of view, she can't grasp that Helmut is actually escaped Nazi Josef Mengele, who's carrying on his experiments with her and her family. Of course, this chills us to the bone, but we also understand why Lilith is drawn to this thoughtful, warm-humoured man whois helping her escape daily bullying for looking like an 8-year-old.

Intriguingly, no one seems terribly bothered to have a Nazi around. This is an area settled by Germans for whom the war was half a world away. And Puenzo's point is that the parents can't see the legacy they give their children by letting them grow up around war criminals. Indeed, Puenzo packs the film with her usual themes of physical and political coming-of-age, as Lilith worries that her own body is betraying her.

The film is beautifully shot in a spectacular location, with warm cinematography that creates an intriguingly nostalgic tone. And the subtle intrigue sneaks up on us. Lilith also doesn't notice that the local photographer (Roger) is actually a Nazi-hunter. Through Lilith's eyes, we can't help but like Helmut, even though we know who he really is. But it's also impossible not to see his yearning for human perfection as a terrifying obsession, since we know he has no limits.