There is something comforting about doctors. Even if they are unable to reassure you that nothing is wrong, they can provide you with answers; they can name your problem and in doing so bring welcome definition to the shapeless fear of the unknown that has been nagging away at you. And in the case of mental illness, “know thyself, know thy enemy” (as the saying goes) is a good place to start. But what if your diagnosis, the label you are given, is motivated not by an uncomplicated desire to help you but by another agenda? What if commercial needs, workplace politics, racial prejudice or personal ambition are the deciding factors? Where does that leave you?

This question is at the heart of Joe Penhall’s darkly comic and superbly written play which was first performed at the National Theatre in 2000 by an all-male cast, and now on at the Arcola Theatre under the direction of Femi Elufowoju, Jr.

Juliet (Ayesha Antoine) is restless. She only has 24 hours left in the London NHS psychiatric hospital to which she has been sectioned by the police, and she is eager to leave. She just needs her doctor, Emily (Esther Hall), to sign her off as suffering from borderline personality disorder and she will be released. Emily, however, believes that Juliet is a paranoid schizophrenic, wants her sectioned for longer, and asks her supervisor, Hilary (Helen Schlesinger), to get involved.

The play goes on to chart Emily’s and Hilary’s increasingly heated disagreement over exactly what is wrong with Juliet – triggered by her insistence that her father is Idi Amin and that the oranges in the consulting room are blue – and the damaging consequences of this dispute.

Language, let alone Juliet, exists on the borderline in Blue/Orange. For the naive Emily, “paranoid schizophrenic” means that her patient is a risk to herself and to others; for Hilary, it means extra hospital beds and expense – a diagnosis of “personality disorder” is her desired outcome and she is determined to see it achieved. The single set of the consulting room soon becomes a battleground in which boundaries are crossed and words are weapons capable of inflicting very real damage.

As played by Schlesinger, Hilary is a whirlwind of designer clothing, laughter and self-assuredness. Initially, she is a refreshing change to the stiff, awkward Emily, making jokes and offering Juliet a banned cup of coffee and a cigarette. But from small gestures, such as moving Emily’s coat to the visitor’s chair before a meeting, through to her angry, almost manic, reminder that she is “the authority” in the hospital, she is revealed to be manipulative and ruthless.

Schlesinger skilfully captures the character’s dangerous charisma, laying on the charm so that the moments when she loses her temper and shows her true colours are all the more disturbing. No less unsettling is the perfunctory manner in which she accuses Emily of “ethnocentricity” to silence her objections to releasing Juliet. And the look of glee on her face at the prospect of using Juliet as a research subject for her thesis on “black psychosis” is queasily lascivious.

Hall, meanwhile, succeeds at the tougher job of breathing life into Emily. This character could have been no more than a cardboard cut-out of the “little man” crushed by the system. Instead, Hall exploits the nuances of Penhall’s script to portray Emily as someone who may be naive but is far from innocent: pacing the stage and gripping her sides as if afraid she will fly apart at any moment, she is just as willing as Hilary to take advantage of Juliet when it seems her job is at risk.

The canniness of recasting male characters as female manifests itself in the tense relationship between Hilary and Emily; the play’s language of one-upmanship is even more effective when set against a backdrop of workplace discrimination and glass ceilings. Emily’s consulting room, colourless and devoid of personal possessions, suggests an impermanence that only reinforces this sense of professional insecurity.

If this production has one flaw it is that it does not always adequately convey the risk presented by Juliet. Antoine, her brow furrowed by suspicion, defensiveness and confusion, is exceptional; stomping around the stage, her Juliet is a proud and conflicted character who is compelling to watch. However, at no point does it feel as though she is capable of harming herself or someone else. Without the reality of her situation acting as a tether, the true weight of the ethical issues being debated is sometimes lost.

Nevertheless, this latest production of Blue/Orange is a triumph. A strong cast and simple yet effective staging bring out the fire in Penhall’s words. Whatever may be wrong with Juliet, it is as nothing compared to her treatment by those in the medical profession who are supposed to be helping her.

(At the Arcola Theatre, 27 October-20 November 2010)

Reviewed for musicOMH