Two young missionaries visit a man at his cavernous house to discuss Mormon doctrines but get drawn into a psychological game of terror and manipulation

The remarkable second act of Hugh Grant’s career continues … or maybe third act, if we include the earlier period in which he appeared to withdraw from the movie romcom-lead frontline to concentrate on making brilliant investments in property and contemporary art, before returning as a lethally outrageous character actor and scene-stealer. Now Grant is making his horror debut (if we don’t include his appearance in Ken Russell’s The Lair of the White Worm from 1988) and does it with typical insouciance and cheek, starring in a verbose and disturbing chamber piece about religion from writer-directors Scott Beck and Bryan Woods; it feels as if George Bernard Shaw wanted to make a scary movie without songs inspired by The Book of Mormon.

Maturity and the chiller genre have added a certain something to Grant’s habitual mannerisms, on display as ever here: the sudden mischievous grin and the wide-eyed conspiratorial “eek!” grimace of mock dismay. He plays a donnish and bespectacled Brit called Mr Reed living in the US in a remote, eccentrically proportioned house. Like Grant’s ageing thespian Phoenix Buchanan in Paddington 2, this man is vain enough to keep a photo of his younger self about the place. Mr Reed has expressed a diffident interest in the Church of Jesus Christ of Latter-day Saints, so the Mormons have sent round two missionaries to discuss this with him; not strapping young men as would normally be the case in non-horror-film real life, but two twentysomething women. These are the innocent Sister Paxton (Chloe East) and the marginally more worldly Sister Barnes (Sophie Thatcher), who in the first scene reacts with unjudging sisterly amusement when Paxton recounts her shock at accidentally watching a porn film and expressing her earnest belief that the female lead’s unsimulated expression of despair proves the need to live a godly life.