Forget, for a moment, everything you know about Hugh Grant. The plummy star of Notting Hill and Love Actually may be best known on screen for his bumbling charm and a twinkling eye but not this week. In cinemas today, Heretic finds a more sinister Grant primed to attack.

From Scott Beck and Bryan Woods, the duo behind A Quiet Place and last year’s The Boogeyman, Heretic sees Grant play the illuminating Mr. Reed. He’s an affable sort, well educated and intellectually curious, but there’s something awry from the off. His home is disquietingly remote and the wife he claims to be home is nowhere to be seen.

The early warning signs are there, then, but don’t deter Mormon missionary duo, Sister Barnes (Yellowjackets’ Sophie Thatcher) and Sister Paxton (The Fabelmans’ Chloe East) in their pursuit of converts. Indeed, the very promise of a Mrs. Reed, ostensibly baking in the room next door, proves sufficient to reassure the pair that no rules will be broken.

A three-way religious discourse starts well enough. Certainly, the conversation is lively and Reed surprisingly well versed in the intricacies of the Mormon way, and yet, the gears of intensity soon shift. Increasingly, Reed questions the moral substance of the Church of the Latter-day Saints, probing at hints of what he perceives to be hypocrisy.

Before they know it, Barnes and Paxton find their exits blocked. All too quickly, the wool is torn from their eyes. Reed’s venomous cat and mouse game is gnarly, the nastiness snowballing. Participation is obligatory.

As is so often the case in such genre fare, Heretic’s revelations haven’t quite the punchy deliverance to match the anticipatory build up of its suspenseful first half. One or two far fetched choices fail, for instance, to convince. The descent into gore is almost a disappointment.

Nevertheless, tremendous performances keep the vim and vigour high. Beyond Grant - clearly having a terrific time throughout - Thatcher and East impress, infusing humour and warmth into roles that dance between predator and prey. They’re all too easy to root for, one bright eyed and bushy tailed, the other rather more browbeaten.

Heretic, then, works best as an actorly drama, a dialogue heavy and almost theatrical experience. Wickedly well-scribed lines pepper Beck and Woods’ script, the comic inflections bolstering the film’s grimmer instincts. It’s a surprisingly pop cultural effort.