JJ (Dommett) knows he's tempting fate when he enters a London rap competition. Not only is he white, but he's also openly gay and attends the final with his boyfriend Orlando (Kai). So rival rap squad the Illmanics (Wharton, Clough, Bonin and Steed) take offence and horrifically bash Orlando backstage, leaving him permanently disabled. Shockingly, the unapologetic attackers receive lenient sentences and will soon be back on the street. So JJ enlists a couple of friends (Daley and Hewitt), and takes an unusual step to diffuse the dangerous tension.

At the centre of the film, there's a bit of heavy irony that closeted gay lawyer Daniel (Lindall), who represented the attackers in court, was himself assaulted by them in the opening scene. And he's the one who approaches JJ with the idea of taking on the violent bigotry in rap music, asking why black culture in particular is so angry and fearful about homosexuality. This leads to a surprising turn of events that feels slightly like a wish-fulfilment fantasy but still has a serious edge to it.

Beadle-Blair keeps the film energetic, colourful and sexy. It's also packed with so many fast-talking characters that it's not always easy to follow. These include people who express their prejudices in a variety of ways, including self-loathing, bravado posturing and physical violence. And as each of the characters goes on an intensely personal journey, the actors remain naturalistic and raw, digging deep inside to pick apart their characters' motivations and attitudes.

This is an impressively complex exploration of a dark shadow that infuses modern society from ignorant schoolyard slang to homophobic laws on the books of hundreds of countries. At times the film feels far too dense, as it only lets up on the serious topics for the occasional lighthearted moment of romance or emotion. But its layered approach lingers in the memory. And it could help change people's hearts.

In the snowy Urals in February 1959, nine hikers were killed in circumstances that were never explained, some of them suffering internal but no external injuries. The mystery has never been solved, so Oregon psychology student Holly (Goss) decides to get some answers, making a documentary with film student Jenson (Stokoe), sound recordist Denise (Atkinson) and hiking experts JP and Andy (Albright and Hawley). But as they head to Russia, their journey starts to take similarly strange twists and turns, until they stumble into the middle of something nefarious.

The script continually drops in references to sinister Soviet government experiments, aliens and even sightings of a yeti, which adds a sense of gleeful fun to the encroaching doom. Harlin also makes terrific use of archive photos and footage of the original expedition, some of which are real. And the locals call the area the "Mountain of the Dead" as they taunt these gung-ho Yanks. But all of this suggestion is far more engaging and creepy than what they discover in the pass.

It's the usual problem: hinting at something nasty is so much more effective than actually showing it to us. The nutty final act here strains to be a brain-bending nightmare, but is actually rather silly. Which is a shame because the build-up is so strong, beautifully photographed in spectacular scenery with a lively young cast we enjoy following, even if their soapy interaction is interrupted by abject chaos.

Harlin packs the film with terrific little touches, from freak-out stories told by various characters to glimpses of things that aren't quite right in the background. As far as found-footage horror goes, this is an extremely well-made movie. And the grisly climactic scenes at least take us somewhere unexpected. So if the conclusion is annoyingly unsatisfying, at least we've had some unnerving fun getting there.

Isabelle (Rapace) is a rising-star at her marketing firm in Berlin, where she works for shrewd boss Christine (McAdams). On a business trip to London, Isabelle has a fling with Christine's boyfriend Dirk (Anderson), then is shocked when Christine steals her latest great idea to get a transfer to New York. So their friendly working rivalry takes a dark turn, as each tries to manipulate or belittle the other. As the bitterness between Isabelle and Christine escalates, things turn very ugly. And Isabelle turns to her too-loyal assistant Dani (Herfurth) for help.

As usual, De Palma's writing and direction are a riot of innuendo and suggestion, although he keeps the pace languid and a bit dull. Long before things turn explosive, we can vividly feel the tensions building up beneath the surface. So the visually subdued approach feels very odd, almost like an underdeveloped low-budget TV movie, complete with a cheesy score. And for a film titled Passion, there's very little on display.

Still, De Palma always casts his leading ladies intriguingly, as McAdams and Rapace seem like flip sides of the same coin, which kind of undermines the boss-employee dynamic. But they create a sharp sense of camaraderie, which adds a sting to the competition between them. Of course, DePalma can't resist adding a sudsy layer of girl-on-girl attraction, as they flirt shamelessly with each other. And there are other tantalising suggestions sprinkled throughout the script, such as the fact that Christine once had a twin sister.

As the rivalry between these women escalates from office politics to romantic betrayal to public humiliation, we know it's only a matter of time before someone turns up dead. Indeed, De Palma uses liberal splashes of bright red to flag up the film's Hitchcockian ambitions. There's even a shower scene (with a red curtain). And Christine continually wakes from nightmares to find that her real life is even scarier.

Crispian (Bowen) is nervous about taking his girlfriend Erin (Vinson) to his family's palatial summer home, where everyone's gathering to celebrate the 35th anniversary of his parents (Moran and Crampton). His three siblings Felix, Aimee and Drake (Tucci, Swanberg and Seimetz) are all on hand with their respective partners (Glenn, Myers and West), and the arguments start with their first meal together. But this is interrupted by an arrow through a window, which is just the beginning as they're picked off one by one. And Erin's the one who fights back.

The set-up couldn't be much more cursory. As the family arrives, everyone has a bad feeling about this. Indeed, their attackers are extremely well-armed with knives and crossbows, smart enough to booby trap the house and dressed like ninjas with animal masks for added freak-out value. All of this is deeply contrived, and it gets sillier when people pick up steak knives to defend themselves when surely a baseball bat is more like it.

The filmmakers seem proud of the fact that they've made a killer-thriller without a single gun. Although the proliferation of machetes and hatchets kind of undermines the point. This is a brutal film that gets even nastier as we learn why this is happening. Yes, the script bothers to include a reason for the carnage. It's not much more complex than the simplistic back-stories, but at least it's there.

Meanwhile, the audience is badly let down by laughably bad performances. The half-hearted direction seems to be waiting for something to happen. Corny script devices like a mobile phone jammer that's clumsily referenced in the dialog. And in post-production, groaning assonance has been added to the soundtrack to remind us that this is supposed to be creepy. Sure, there are a couple of mild surprises along the way, but it would be a lot more effective if we couldn't tell from the moment the film starts exactly what will happen next.