You don’t need to have your finger on the political pulse to know that the country is at a critical moment in its history. And because theatre makers often consider it their role, nay duty, to reflect the nation, playwrights are these days holding a mirror up to Britain as if it were a patient breathing its last.

The latest to do this is Mike Bartlett, creator and writer of Doctor Foster, a marriage-gone-terrifyingly-wrong TV drama that, despite its credulity-stretching plot, has twice gripped the nation.

In his latest play the landscape is much broader, even if its physical territory is restricted to the dilapidated garden of a grand country house.

The pile has been bought by businesswoman Audrey (Victoria Hamilton) who has moved there from London with her reluctant daughter Zara (Charlotte Hope). Audrey is on a mission. The house once belonged to her uncle and she is determined to revive what she thinks of as an idyllic, quintessentially Englishness that she remembers from childhood visits to the house.

So we have a play called Albion (an archaic name for Britain), a patch of green and pleasant land, and Audrey who is driven to renovate it by a proud nostalgia for an England that has been all but lost. Everything here, it seems, has a double meaning. Audrey has a new Polish cleaner Krystyna, played by a pitch-perfect Edyta Budnik who captures exactly the single-minded work ethic of so many eastern European migrants. But her purpose in the play is to represent Brexit Britain. Or at least something that might be lost to the country if she were to be forced to leave. English rose Zara looks positively feckless by comparison.

Meanwhile, Audrey — played by Hamilton with charismatic haughtiness — conscripts everyone to her task. The garden is steeped in emotive English history. It used to be a memorial for Britain’s First World War dead. Now it is also the final resting place of Audrey’s soldier son who died in action. She scattered his ashes among the borders, much to the disapproval of his still-grieving girlfriend Anna (Vinette Robinson) who had her own plans for the remains.

You can’t fault the skill with which this play and production has been constructed. It contains one of the few genuine theatrical coups of the year when the unhinged Anna loses control of her grief, engorging herself with the soil that now contains her lost lover.

And there are compelling conflicts, not least between Audrey and her visiting novelist friend Katherine (Helen Schlesinger) whose latest work satirises the small minded Englishness that has taken control of her country. So that’s Remainers accounted for too.

Clearly, no one can doubt the relevance of this play. Yet all this rather obvious box-ticking prevents it from becoming greater than the sum of its symbolic parts. Or, put another way, it’s impossible to be unaware of its artifice.

Director Rupert Goold ensures that three hours zip by, not least with an evocative use of stirring music such as the thumping Blood Hands by the rock duo Royal Blood to which Zara becomes dangerously overcome with grief.

But although the production is superbly acted, these characters never really escape the symbols they were created to represent. They’re never just, well, people.