Staircase @ The Tron

Usually, l despise portrayals of mental illness on stage. All too often, madness is a signifier: an actor shouts a bit, maybe throws in a distinctive twitch and the play's ill-conceived moments of surrealism are excused. It's insulting and, as in the case of many productions of Greek tragedies involving the character of Cassandra, evidence that the director knows nothing about mental health and hasn't read the script properly.

Andy Arnold's production of Staircase is an elegantly disguised representation of madness, disguised as a period tragedy of manners. It is a form of stage madness - the main character's insanity is far too theatrical to appear in any textbook for psychiatrists - but Arnold's performance is assured and reveals the underlying anxieties in moments of graceful despair. The insanity is so well hidden that it is invisible for most of the play, and the revelation is excellently handled.

On the surface, Staircase is a period piece: a couple of homosexual men live in fear of exposure in 1960s London. The sharp banter - Arnold selects his scripts with an eye for the language - twists around the comfortable conflicts of the well-worn couple and the broader menace of a society that still saw gay love as a crime, while Arnold and Benny Young evoke a lost period of gentility and repression precisely.

The last quarter of an hour throws up, gently, questions about the role of creativity in mundane life - Arnold's character shares the name of the author, and his stifled ambitions to act are channelled into self-destructive fantasy. By refusing to update or trivialise the context, however, Arnold has created two works in one: a study of 1960s' sexual mores and a moving tale of creepin insanity that goes beyond its historical detail.