While working on a human geography project as part of her studies, Nikki (Press) travels to an isolated Scottish island and presents herself as a prospective tenant at isolated house owned by her birth mother Phyllis (McTeer), who doesn't recognise her. As she plots her revenge against the woman who abandoned her, she's surprised to discover that she has a brother, Calum (Morgan). But her continual questions about their husband-father are blanked, and life on the island becomes increasingly intriguing as she seeks answers about her past.

Directors Taylor and Mitchell use grey-tinged cinematography and an oppressively creepy sound-mix to create a jittery, dark visual style. It's seriously bleak and portentous, with foreboding skies constantly reminding us that there's no way this can end happily. Not that it's ever remotely happy along the way. But at least the mystery is compelling, keeping us guessing with half-answered questions, vague suggestions, hesitant conversations, haunting flashbacks and folk tales illustrated with inky animation.

Nikki's deep bitterness is complicated and intriguing; she wants to get even for her lifetime of misery, but is increasingly drawn to these people and this place. Meanwhile, Calum has a disarming innocence that's slightly unbalanced. But this is nothing compared to his haunted, witchy mum, who keeps him on a tight leash amid her violent mood swings. All three performances are packed with jarring touches that border on camp.

In fact, the whole film is rather arch and gothic, and overplayed by the directors as well as the cast members. It's not particularly scary, but the fear in Nikki's eyes is pretty unsettling, and Press plays her with a haunted quality that's not always easy to watch. But the key action-oriented scenes are shot and edited in such a way that it's impossible to see quite what is happening. And the story takes some very dark turns that stretch our sympathy to the breaking point.

After his tour of duty in Iraq, David (Muxworthy) rides his mountain bike into the Italian Alps. At an isolated tavern called The Shadow, he meets the sparky-sexy Angeline (Testa), but they quickly annoy a pair of vicious hunters (Coppola and Blitch). So when their paths cross again in the woods, the bikers become the prey, riding straight into a shadowy, mysterious part of the mountains reportedly haunted by vengeful war dead. If only. Even with meeting the hot Angeline, this isn't the mind-clearing getaway David had in mind.

Popstar Zampaglione clearly enjoys constantly unsettling us, from sudden noises to glimpses of rusty blades, plus flashbacks to the battlefield and overly masculine, gun-happy thugs. And then there's the sadistic bald nutcase (Arquint) who appears out of nowhere and tries to divert the movie into the Saw franchise. Some of this is very cheesy: this is Italy, but everyone speaks English, and the hunters drive a Jeep festooned with both the US and Confederate flags, as well as the Union Jack.

Strangely, virtually every element comes from bad American horror, recycling cliches and ideas while aiming at the least observant audience imaginable. That said, the cinematography is gorgeous, and the film is strikingly well edited to build a sense of dread as things continually go bump in the night or rustle the leaves in the foggy gloom. Muxworthy underplays his role very nicely indeed while everyone around him ramps up the testosterone, including Testa. Arquint is just plain weird.

As it progresses, the competent filmmaking keeps us interested, especially since we're never sure where it's going next. And the increasingly hideous grisliness will entertain horror fans up until the big-shift ending. Most of this isn't actually very explicit, but that makes it even more wince-inducing. The real problem, besides a lack of originality, is that we don't really know any of the characters at all. So the film's main message seems to be: don't lick the frog.

After his family is killed, teen Martin (Paolo) is taken under the wing of Mister (Damici), a gruff hunter who mercilessly stalks vampire/zombies. As they cross middle America in search of a rumoured safe zone called New Eden, they meet a friendly nun (McGillis), an ex-marine (Nelson) and a hot pregnant teen (Harris). They also run afoul of an extremist religious cult led by the vicious Jebedia (Cerveris), who believes the vampires are God's judgement on society. And he starts hunting the hunters.

It's the same essential plot as Zombieland, as the characters travel from one devastated town to another in search of some sign of humanity. That the largest society they encounter consists of gun-toting fanatics is a cruel joke. But this movie isn't trying to make us laugh. And the vampires' relentless craving for human blood has rendered them as crazed addicts, mutely staggering across the landscape like the infected undead in 28 Days Later.

Filmmakers Mickle and Damici keep us on our toes all the way through, opting for a serious approach that gives the film some gravitas, especially as the story touches on big issues like religious fanaticism and the nature of civilisation. While the script is relatively superficial and over-reliant on Martin's narration, it deepens the characters as it goes along, which makes the later scenes surprisingly moving.

The anecdotal narrative is packed with outrageous set pieces that push things in intriguing directions, such as the quarantined small-town party that's horrifically interrupted by helicopters. Or the young female vampire in an abandoned house who's eerily seductive. The cast engages our sympathies early on (McGillis is especially good), which makes everything that happens thoroughly involving. Although Paolo seems closer to 20 than "just a boy". And the fact that he finds a sexy love interest in the middle of all of this squalor is a bit ridiculous. Then a vampire Santa appears to get us back in the mood.

Bobby (Kebbel) returns from his final tour of duty in Afghanistan with no plans for his life, although two separate groups make rather insistent offers. First there's the top thug (Thomas) on his grim South London estate, who requires him to join his gun-toting heavies. But Bobby instead wants to help the little brother (Ayemere) of his friend Fahad (Jeremiah), get out of the gang. Meanwhile, government agents (Curran and Cox) ask him to help shut down a terrorist cell by contacting their rogue informant Alayna (Bielski). But all of this smells fishy.

Filmmaker Hope shoots this like a post-apocalyptic nightmare, in which present-day London looks like a terrifying dystopia where heavily armed goons shoot and stab each other on every street corner. Filmed on a condemned Elephant & Castle estate, it's a thoroughly unnerving atmosphere, as we feel the desperation in the air. We also vividly sense the tentacles of crime and low-life nastiness that are squeezing in on Bobby from every side. He clearly wants to do the right thing, but isn't given much of a choice.

Kebbell plays the character extremely effectively as a scruffy guy who has the brains and physical prowess to do these violent jobs, but feels emotionally shattered by his war-zone experiences. So he's a bundle of flippant intensity and hollow exhaustion. His interaction with everyone snaps with raw internal energy, especially scenes with Bielski, who's equally complex and enigmatic. Brooke is solid as well as Bobby's old pal who clearly regrets getting his friend involved in all of this.

By contrast, Curran and Cox are required only to provide some effectively starry texture as "the man". And as things escalate, there's the sense that the filmmakers are kind of skating over some of the plot's implausibilities, never quite defining the events fully while offering some strongly preachy moments along the way to make sure we get the point. But at least the point is a resonant, important one. And Bobby's story is seriously unnerving.