Apostasy review - trouble in the Jehovah's Witnesses' Kingdom

Religion’s desire to fulfil humanity too often denies it instead. The cruelty of inflexible faith which breaks fallible adherents on its iron rules is at the core of this family drama, written and directed by former Jehovah’s Witness Daniel Kokotajlo.

At times it seems a fictionalised, fly on the wall documentary on a secretive sect. More often, it’s a meditation on its female protagonists, observing their struggle in the flytrap of an unusual community.

Alex Whitling (Molly Wright) has turned 18 when we meet her, an occasion marked not by wild partying, but her legal confirmation that she will refuse blood transfusions, despite her anaemia. She mistily turns the pages of a book of martyrs to this eccentric article of Jehovah’s Witness faith, encouraged by devout mum Ivanna (Siobhan Finneran). Her more outgoing older sister Luisa (Sacha Parkinson, pictured below between Finneran and Wright) is having her questioning nature stimulated at college, even as the siblings still knock on doors together in their Oldham neighbourhood, keenly spreading the Kingdom’s word in Urdu to bemused Muslims.

Complicit, loving looks pass between the sisters, in a home where background sound and small talk are in short supply. Frequent close-ups emphasise the vulnerable softness of Alex’s skin and matching, bashful good nature, and Ivanna’s pained, dutiful obedience to the Elders: mostly bluff Northern burghers whose word is law.

Ivanna’s contempt for “airy-fairy Catholics”, and scenes of Witnesses down the pub, are among the humorous incongruities Kokotajlo’s inside knowledge allows. The individuals behind the Watchtower-selling zealots most only see on their doorsteps include a more boisterous family who drink cider and dance to (Witness-appopriate) rock music, and awkward young Elder Steven (Robert Emms, pictured below with Finneran), just up from the South and shyly keen on Alex.

The Elders’ disfellowship of Luisa when she becomes pregnant by an outsider is one of two exhausting tests of faith for the family. The flipside of the loving community they feel part of is shown by this cruel casting out, which requires Ivanna to ignore her daughter. Even ordinary, well-meaning Steven’s kindness runs out with his faith’s tolerance of human nature. As Luisa says when she confronts her mum over the inconsistencies and narrowness which mar the religion they once shared, its leaders have made things up on the fly, jury-rigging bizarre extensions to Christianity which, if you’re pregnant or anaemic, can have terrible consequences.

This is a brave and awkward project for Kokotaljo to take on as his debut, though perhaps a necessary one. He rarely abandons sympathy for any of his characters, a Christian tenet in short supply in the film’s Kingdom Hall. He shows that you can believe the End of Days is imminent and still want to get your nails done, and love someone but reject them before you’ll let your faith’s walls crash down. The director’s sonic austerity and sensual attention to people, moorland vistas and rustling canopies of leaves conjures a rich world around the Whitlings. He considers a society he left with the ambiguity it lacks.

• More film reviews on theartsdesk