Agatha Christie is the queen of crime, with a knack for pulling the (wonderfully art deco) rug out from beneath readers time and time again. This feat is not limited just to her books, as Love from a Stranger proves; although there is no mention of Poirot or Marple, this play carries every hallmark of a Christie masterpiece – intrigue, a gripping storyline, and an American man whose friendly manner is a little bit too friendly.

This iteration, directed by Lucy Bailey, sets the atmosphere from the get-go: the stage is plunged into darkness as shadowy figures move around wordlessly. When the lights come back up, it becomes clear that the figures are nothing more than an overly chatty aunt and a well-mannered friend packing up an apartment – yet it plants an idea in the audience’s minds that perhaps all is not what it seems here.

Helen Bradbury, playing the protagonist Cecily Harrington, is excellent. She flits between girlish and detached, much to the despair of her friend Mavis (Alice Haig) and fiancé Michael (Justin Avoth). She manages to pull the audience in and shut them out by turn. She infuriates us in act one and then, despite her foolishness, still convinces us to root for her in the second half. Her vapid, careless mannerisms shift as she realises the full extent of her mistake – nervous housekeepers wishing her good luck, an erratic doctor who always seems to be holding something back, an isolated cottage with no telephone just some of the clues.

As the pieces slot into place, and Cecily’s life with her new husband Bruce (Sam Frenchum) begins to unravel, aspects of the set that have featured throughout the entire play take on a new, sinister meaning. The LED strip lighting that runs around the walls turns red – like Bruce’s beloved dark room – and the sliding stage, which was previously charming, becomes claustrophobic as Cecily is stalked from room to room by a man she seemingly doesn’t know – or trust – at all. When Bruce cheerfully calls out, “Darling, I locked the back door while we were getting coffee!”, the audience experiences a real thrill of dread at Cecily’s gradually mounting panic.

It is a delightfully macabre play, and Christie’s setups are like no other. Just as we think the story will be tied up nicely, with Cecily’s jilted ex-fiancé rushing in to save the day, the tables are turned yet again. And as the curtain drops on a stunned Mavis and Michael, Cecily covers her mouth and turns away from the audience – unreachable once again.