Ten years after its premiere at the National Theatre, Joe Penhall’s enthralling Blue/Orange makes a comeback in a production from the Tiata Fahodzi company directed by Femi Elufowoju, jr, that re-casts the male patient and two male doctors as female.

Less is lost in this transposition than might have been in, say, The Caretaker; Penhall is less “bloke-ish” a writer than Pinter. But there’s still a faint whiff of implausibility in the treatment of 24-year-old Juliet, the borderline psychotic who is being discharged into the community – or is she? – after being sectioned.

Juliet (as opposed to Christopher) is now the daughter of Idi Amin, she says, not the son of Idi’s fifth wife living in Feltham, which sounded less unlikely before. And she still thinks that the oranges are blue, a sign from her father and another symptom of what the senior consultant, Hilary (Helen Schlesinger) describes as “black psychosis.”

The first production marked the breakthrough performance of Chiwetel Ejiofor and was electrifyingly presented in a cockpit arena by director Roger Michell. Here, the battleground occupied by Hilary and the young doctor, Emily (Esther Hall) is less ferocious in Ultz’s expensive-looking white box design through which we peer like voyeurs on all four sides.

Still, this remains a marvellous feat of writing in its use of the language of therapy, and in the way it whips up a professional storm over one patient and, increasingly, the two doctors’ careers and reputations.

In Juliet’s case, the emphasis now shifts towards the idea of her Muslim fundamentalism, but Ayesha Antoine’s admirably fiery and energetic performance doesn’t solve the mystery of why exactly she is so angry about everything.