There’s no more frightening moment in the intriguing new Irish horror flick Citadel than the opening scene. A young man (Aneurin Barnard) waves goodbye to his pregnant young wife in their new apartment. He walks onto the elevator and then looks back to see a group young folks with hoodies pounce on his love. He can’t open the elevator though and has to painfully wait for it to trudge to the ground floor before running up the stairs at top speed. He finds his wife unconscious with a hypodermic needle sticking out of her pregnant belly. Yikes. Citadel never quite lives up to that chilling opening (apparently inspired by a mugging writer/director Ciaran Foy experienced), but it does settle into a satisfyingly creepy groove that qualifies as a strong genre debut for Foy. This is one of those creepy kid horror movies, but times have changed since the blond British monotone psychics of The Village of the Damned. These days creepy kids come in hoodies and like to terrorize upstanding folks in the community just for being old (see Eden Lake and Them for more). Citadel takes that slowly growing trend and throws in a demonic twist just for fun.

Barnard is obviously a bit shaken up by the whole murdered girlfriend thing, and is left scarred by agoraphobia while trying to raise his prematurely born child. He starts to get a little better at the whole “going outside” thing thanks to the help of a kindly nurse (Wunmi Mosaku), but that quickly goes away once those pesky kids starts showing up and frightening him again. Eventually he turns to a priest for help (James Cosmo). Unfortunately that priest is a bit crazy, but luckily he’s also equally obsessed with the terrorizing teens and has an intriguing theory. Cosmo thinks the dejected and impoverished youngsters have been possessed by demons and only he and Barnard can stop them. With the help of a blind boy (Jake Wilson) who was rescued from the evil children’s clutches, the guys set out to the derelict high-rise to destroy the demonic punks once and for all. Given that Barnard is a shaken and possibly insane protagonist, it’s never clear if the whole horror tale is actually happening outside of his mind, but either way it’s a wild ride to salvation.

Foy shoots his no-budget effort with jittery handheld cameras to match Barnard’s fractured mental state. It’s an aesthetic that has been exploited to death in the 2000s, but Foy at least has material to suit the style and knows how to shoot in shaky-cam while still allowing the audience to see what’s happening. The film hints at subtexts about a generation of rejected impoverished kids acting out violent crimes in frustration, but never gets too lost in social commentary over genre thrills. It’s fairly straightforward horror fare, but executed well. Foy knows how to generate suspense and can deliver a good bloody set piece when required. His possessed youths are grotesque creations and never shown too much or over-explained through backstory. They’re simply a frightening, unseen hooded force and you don’t really need much else than that in a 90-minute suspense/horror picture.

Barnard does an admirable job of playing a character perpetually on edge and in a state of shock without straying into Nicolas Cage territory. He’s got a knack for keeping hysteria grounded and provides the strong core the film needs. Cosmo is quite amusing and the fire and brimstone priest out for blood, delivering speeches with gravelly voiced gravitas and creating a strong willed hero to drag the whimpering Barnard through to the finish line. The rest of the cast isn’t really on screen enough to make much of an impact, but kudos to whoever found the kids to play the demons. Those youngsters manage to make hoodies scary again.

Citadel is a horror movie deeply indebted to past efforts in the genre that might never quite transcend its influences, but at least it delivers the required shocks effectively. Foy succeeds in telling a simple horror story with skill, precision, and brevity, which is much rarer than it sounds. The film delivers its biggest punch in the first scene and then steadily draws out more without ever testing the audience’s patience or being weighed down by clichés. That there’s even the suggestion of social commentary at all is a big bonus. It’s an effective and efficient debut for Foy that might not see him burst onto the genre scene with a new classic, but at least sets the stage for what could be an interesting career. He’s clearly a new horror filmmaker with talent, ambition, and skill. Now it’s just a matter of whether or not he can back up all that promise with a fresh idea. Citadel is good enough to suggest he has that in him, let’s just hope the film is successful enough for the youngster to get a chance to deliver something more substantial next time.