Amid a starry cast, Edgar-Jones especially gives a "beautifully understated" turn as a woman struggling with same-sex attraction – but there's too much plot for the film's own good. In its bare-bones plot, On Swift Horses sounds like a love triangle, or maybe quadrangle, set in the repressed 1950s. Daisy Edgar-Jones and Will Poulter play Muriel and Lee, young marrieds who move from Kansas to California, and Jacob Elordi plays Lee's brother, Julius.

It is clear from the start that Muriel is more dutiful than excited about marrying Lee, and that there is a strong connection between her and her brother-in-law. Instead of focusing, predictably, on that triangle, with Muriel at the centre, the film attempts something more subtle and complicated. The spark between Muriel and Julius is not sexual.

He goes to Las Vegas, where he enters a passionate relationship with Henry (Diego Calva), while Muriel grapples with her own unhappiness and attraction to women. It is a story of subterfuge, secrets and recognitions hardly ever spoken out loud. And it works much better as an idea than as a film.

Despite Edgar-Jones's beautifully understated performance, On Swift Horses only sporadically comes to life. Its sluggish pacing makes it feel pedestrian. The style is not natural or convincing enough to take us into its fictional world, yet it is not stylised enough to be poetic.

The director, Daniel Minahan, best known for television series including Fellow Travelers, has put together a film tha.