Primal fears take root deep in our psyches and occasionally percolate to the surface many years after we have put away our childish things.

Few of these irrational thoughts are more potent than nightmarish images of monsters lurking in the dark.

Nyctophobia is perfectly understandable: we are most vulnerable at night when the world around us is shrouded in inky black and predators hunt unseen by the human eye.

See no evil but hear it, and our febrile imaginations conjure horrific scenarios to shred the steeliest nerves.

Screenwriters Nicolas Casariego and Jaime Marques tap into this universal fear in Intruders, an efficient horror thriller about two children, worlds apart, who are haunted by the same gnarly-fingered bogeyman that rips off the faces of unsuspecting tykes as they sleep.

Spanish director Juan Carlos Fresnadillo, who spilt copious blood at the helm of zombie sequel 28 Weeks Later, cranks up the tension in the chilling opening frames, set in a Madrid apartment block.

A seven-year-old Spanish boy called Juan (Izan Corchero) tells his mother Luisa (Pilar Lopez de Ayala) a ghost story about a disfigured creature called Hollowface.

‘No dreaming about monsters, okay?’ smiles Luisa as she tucks the boy up for the night, leaving a window ajar so the family cat, Meow, can return from its nocturnal slinking.

Sure enough, Juan is woken by the pet’s cries and he climbs onto scaffolding outside of his bedroom window to be greeted by the hideous sight of Hollowface clambering up the metal structure.

Hundreds of miles away on the outskirts of London, 12-year-old Mia Farrow (Ella Purnell) discovers a story lodged in a tree and recites the text to her class, giving birth to the same demon.

‘Monsters are cowards.

If you stand up to them, they run away,’ Mia’s father John (Clive Owen) assures his little girl.

Yet still she senses Hollowface hiding in her bedroom wardrobe.

As both children’s mental condition deteriorates, Luisa turns to local priest Father Antonio (Daniel Bruhl) for salvation while John and his wife Susanna (Carice van Houten) hope psychiatrist Dr Rachel (Kerry Fox) will vanquish the creature that stalks Mia’s waking dreams.

Intruders gets under our skin, introducing discordant strings on the soundtrack every time someone strays into a poorly lit nook.

Scenes involving the two children are particularly unnerving, especially when Juan heeds the advice of his mother (‘Close your eyes and count to five.

When you open them, he’ll be gone!’) and discovers how wrong she is.

Performances are solid if unremarkable, teetering on the brink of unintentional hilarity as the screenwriters attempt to glue together the two plot strands with some bona fide science.

‘They’re both nuts, the boy and the mother!’ barks an elderly priest after his first-hand encounter with Luisa and Juan.

Amen.

• Release Date: Friday 27 January 2012
• Certificate: 15
• Runtime: 100mins