Rust review: Admirably precise but promises more than it delivers

It’s the Betrayal question respun for the smartphone age: how does any adulterous couple in London nowadays manage to afford a sneaky studio flat for their weekly assignations?

Writer Kenny Emson doesn’t explain, other than to suggest that Nadia (Claire Lams), refreshingly the driving force in this relationship, is wealthy and high-achieving.

Over a series of 20 short scenes, Emson tracks the rise and otherwise of the affair between Nadia and Daniel (Jon Foster), a clock repairer. It’s hard to envisage how this pair ever met but, never mind, here they are in their new flat, which is represented by a big pile of pillows centre stage. Try as they might to create a hermetically sealed cocoon, the outside world and their outside lives insist on encroaching.

Director Eleanor Rhode creates an admirably precise delineation of mood at the start of each scene, moods that are nearly always determined by the volatile Nadia.

Lams is persuasive as a mischievous free spirit railing against the constraints of married life but even so Rust promises far more than it delivers.

Until July 27 (020 8743 5050, bushtheatre.co.uk)