Belleville, Donmar Warehouse, London, theatre review: 'The acting is terrific'

James Norton and Imogen Poots shine in Amy Herzog's study of a young marriage beginning to unravel

Imogen Poots (Abby) and James Norton (Zack) in Belleville at the Donmar Warehouse (Marc Brenner)

James Norton and Imogen Poots excel as fraught Americans in Paris in Amy Herzog's sharp-eared study of a young marriage that is starting to unravel. On the face of it, Zack and Abby are living the expat dream. They have moved to Paris so that he can take up important work in paediatric Aids care with Medecins Sans Frontieres, She's an actress who also teaches yoga. But there is unease from the first moments when we see Abby returning early to their boho flat in Belleville (no one showed up to her Yoga class) and catching Zack having some intimate moments with his laptop. What's he doing home from work in the afternoon?

The pair are young (28 years old) and cute – and live in a bubble of relative entitlement, as the play shows by contrasting them with their landlords, Alioune (Malachi Kirby) and Amina (Faith Alabi), the Senegalese-French couple who are largely encountered in their dutiful professional capacities. We learn, thriller-fashion, that Zack, unbeknownst to his wife, is badly behind with the rent. It's one of the secrets that gets swept under the coverlet of the slightly cloying closeness (they call each other “homie”) with which they disguise the extent to which they are skidding into crisis.

Norton signals subtly the controlling side of Zack's husbandly solicitude and the underlying quiet desperation (he's restless and rattled to discover that he's run out of weed). Many of Abby's problems seem to stem from the death from cancer of her mother a few years before (the marriage itself may have been an attempt to brighten up the woman's last days – a grotesque miscalculation). Zack tries to confiscate her mobile phone with which she has a pathological obsession – calls coming in from her father, day and night, about her sister's labour; Zack wants her to start back on her meds. He's manipulatively jealous when she puts on a sexy shirt that she wore when they last went out to dinner with her ex-boyfriend Charlie. He looks completely drained of strength when certain truths come to light. He captures the mix of vulnerability and faint threat beautifully.

Poots's character has to hobble round with a badly stubbed and infected toe and to throw up after a drunk scene. She carries off this septic slapstick with aplomb but is even better at projecting Amy's stung intelligence and her affronted awareness that youthful choices are sometimes disastrous and require a wobbling edifice of deceit to support. She blurts things out with a brusque cruel candour: “I'm so tired of this fucking pressure to be happy. I am not happy, okay, that's just not my, like, mode of being, so if that's what you are trying to accomplish, Stop”. Now she's telling us.

For my taste, the final scenes are overly melodramatic – simplifying what had been complex – and I am not sure that the entire set-up bears much scrutiny when you ponder it afterwards. But Herzog has an excruciatingly good ear for marital strains; the acting is terrific; and Michael Longhurst paces the show absorbingly.

Until 3 February, 020 3282 3808, donmarwarehouse.com