In “Not In Front of the Audience”, Nicholas de Jongh’s 1992 book about homosexuality on stage, there is no mention of John Gielgud’s 1953 arrest and conviction for “importuning male persons for an immoral purpose”.

It was a significant event in Gielgud’s career and in queer British history, but its omission highlights the respect and courtesy Gielgud commanded during his lifetime.

De Jongh finally gets to address the omission in his new play Plague Over England, first performed at the Finborough Theatre and now at the Duchess Theatre for a limited run.

First things first, de Jongh is a highly established and opinionated theatre critic for the Evening Standard and this is his first full length play, so he gets points for bravery before he’s even started. The fact that it’s a good play, and about a subject he is knowledgeable and feels passionate about, is more the better.

It’s an old fashioned drama in many respects, which suits the subject matter and works well with Gielgud as the main protagonist. It has the feel of a Rodney Ackland piece, with the drinking club scenes more than a nod to Absolute Hell.

Michael Feast slips in and out of Gielgud’s mellifluous tones but more than manages to carry the play as he moves from arrogant stage superstar and recently knighted member of the establishment, to a man whose career is in tatters thanks to his entrapment in a toilet in Chelsea by a rather fine looking policeman and the homophobic bigotry of the Establishment.

De Jongh never really delves below the surface of why Gielgud chose the “cottaging” of men’s toilets as his sexual peccadillo rather than other, less risky means of meeting men, and this might have shone further light on Gielgud as a man. But we certainly feel the after effects of guilt, fear and loss from his “moment of madness”.

One of the best things in the play is Celia Imrie, always teetering on the edge of comedy in a similar way to her other Victoria Wood stable mate Julie Walters, but that’s no bad thing. Her Sybil Thorndike is a bastion of no nonsense theatrical loyalty, and she easily morphs into drag queen-esque gay bar owner Vera Dromgoole.

Once again David Burt is present, underused but wholly competent in a production. The bit parts he plays nicely segue together under the banner of “the enemy within”, as he rolls out gay toilet attendants, barmen, waiters and gentleman companions. He highlights the ironies inherent in a ruling class determined to eradicate the growing scourge of homosexuality, whilst being infiltrated at every level, from policemen to the son’s of bigoted judges.

Other well judged performances include Simon Dutton as Percival Lightbourne and Binkie Beaumont and John Warnaby as Chiltern Moncrieffe.

The play’s slightly surreal ending did not feel particularly satisfying given the world of the well made play we had been cocooned in. But it proves a nice metaphor for the changes in society – and in theatre – there were coming. You feel unnerved and disorientated and see the world changing in front of your eyes.

Plague Over England. The Duchess Theatre

BOOK TICKETS TO PLAGUE OVER ENGLAND FROM ONLY £12.50