Imagine that, in the week after the European Union referendum, poet laureate Carol Ann Duffy had published verses in which the symbolic figure of Britannia reflected on the wildly different responses from different parts of her realm. Such a publication might have ranked among the great literary interventions in politics.

Instead, nine months after the vote, Duffy has collaborated with National Theatre artistic director Rufus Norris on an 80-minute play, based on a vast archive of post-referendum interviews, conducted by NT volunteers, with voters around the United Kingdom.

Britannia (Penny Layden) invites representatives of Scotland, the North East, Northern Ireland, Wales, the East Midlands and the South West to a sort of emergency council meeting at which they present quotations from interviews recorded in their area.

Vox pops are always problematic. One difficulty is statistical reliability: in those TV news reports that declare “in Bury market this morning, opinion on the Budget was divided”, the standard two pro voices and the two anti reflect rules on impartiality, rather than balance of opinion. But at least we can be guided by the age, race, demeanour and delivery of the speaker. Norris has opted for a babel of statements, in which we usually know where the contribution is coming from only in geographical terms. This lack of attribution was possibly intended to encourage a purer interpretation of the views – removing prejudices of class or any other caste – but it proves dramatically and journalistically disastrous. As we have no investment in the characters, their arguments are weightless.