Slaughterhouse Rulez

(Cert 15, 104 mins)

There are few tricks and no treats in writer-director Crispian Mills’s painfully outdated horror comedy set at an elite seat of learning for future prime ministers in leafy Gloucestershire.

From the moment Michael Sheen wafts into view as the school’s moneygrabbing headmaster, who forgets that girls have been permitted into the hallowed halls, Slaughterhouse Rulez goes into special measures.

The script grinds through two gears – pedestrian and frenetic – and signposts deaths by positioning cast in front of a door or window so they can be torn limb from limb by carnivorous beasts, which emerge from a fracking sinkhole.

Simon Pegg and Nick Frost co-star as misfits at the centre of the copious blood-letting but this is definitely not another instalment of the duo’s Three Flavours Cornetto trilogy comprising Shaun Of The Dead, Hot Fuzz and The World’s End. They share one brief and superfluous scene, which is notable for an uncomfortable absence of laughs.

More troubling, Mills engineers a fight with one critter which – supposedly – necessitates actress Hermione Corfield losing her schoolgirl’s blouse so the camera and co-stars can ogle her exposed body.

If a male character offered his shirt in response and went topless to defend her honour, perhaps the scene might not feel so grubby and leering.

Don Wallace (Finn Cole) is crestfallen when his mum Babs (Jo Hartley) secures him a last-minute bed at Slaughterhouse School, where cadet training and golf are part of the curriculum.

“It’s like a very exclusive holiday camp!” Babs promises, leaving her boy in the hands of well-to-do room-mate Willoughby (Asa Butterfield). He educates Don on Slaughterhouse’s pecking order with runts like them at the bottom and sixth-formers at the top, including goddess-like Clemsie Lawrence (Corfield) and sadistic prefect Clegg (Tom Rhys Harries).

Don struggles to acclimatise under the reign of headmaster Mr Chapman, aka The Bat (Sheen), who has forged an unholy alliance with Terrafrack to generate funds for “a dry ski slope and the long overdue prefect spa”.

Drilling in nearby woods opens a sinkhole, which anti-fracking activist Woody (Frost) predicts is “a portal that leads right down to hell!”

Disfigured beasts which inhabit a labyrinthine cave network beneath the school emerge from the sinkhole to eviscerate terrified pupils and staff.

Slaughterhouse Rulez settles for gore over giggles.

Cole and Butterfield come close to making us care about their plucky protagonists, whose young lives have been touched by tragedy. We share their doom-laden outlooks before the end credits roll.

Michael Sheen as the headmaster.