Bernard Pomerance suffers from what might be called Harper Lee Syndrome, known for one influential, acclaimed and popular work and little else, though the internet informs us that other plays of his were also staged by experimental theatre group Foco Novo. However, 30 years on, The Elephant Man remains a vital and enthralling play, certainly in its triumphant realisation by Sheffield Theatres.

It would surely be impossible to make a dull play out of the story of Joseph (or John) Merrick, the Elephant Man – a story that was far less well known before Pomerance’s play. Hideously disfigured by a disorder that defied diagnosis, Merrick was rescued from the Victorian world of freak shows by Frederick Treves, the distinguished surgeon of the London Hospital. Doomed to an early death because of his physiological abnormalities, Merrick spent his last years in some comfort, feted by the great and the good.

The Elephant Man concentrates mainly on the London Hospital years, using the case to explore issues of the nature of humanity and the motors of social intercourse. Treves is as important a character as Merrick, some of his insouciant urbanity transferred to his patient with the passing years. All the distinguished patrons find in Merrick a mirror of themselves and Ross, the showman, questions whether there is any change from Merrick’s role as a sideshow.

Possibly the moral debate could prove a bit wordy with the wrong direction, but this is never a danger in Ellie Jones’ inventive production. The hard-working cast of nine populates a world of squalor and splendour, while Dominic Haslam’s haunting musical pastiches and Ellen Cairns’ wonderfully evocative broken pavilion of pleasure prove that, though you can take the man out of the fairground, you can’t take the fairground out of the man.

At the centre of it all are two outstanding performances. As Pomerance specified, Joe Duttine as Merrick is not helped by any special make-up, but transforms himself before our eyes as images of the real man are shown. His remarkable performance is terrifyingly convincing, extremely moving and relieved by a sly wit. Antony Byrne expertly charts Treves’ journey from complacency and content to wracking self-doubt, notably in a chilling dream sequence where he and Merrick change roles.

In an exemplary supporting cast, Paul Moriarty drains the last drop of bluff pragmatism out of Carr Gom, the hospital administrator, and Catherine Kanter explores the border between theatricality and sincerity as Mrs Kendal, the famous actress who introduces the only note of sensuality into Merrick’s life.

- Ron Simpson (reviewed at the Lyceum Theatre, Sheffield)