Do try your best never to be admitted to a psychiatric hospital. That's the message of Joe Penhall's savage satire at the Theatre Royal this week.

If you are admitted, you are likely to be trapped in a complex web of your own illness and the conflicts and jealousies of the psychiatrists treating you.

This award-winning play, first seen in the West End five years ago, has been revived by director Kathy Burke, best known for her comedy roles as Linda in Gimme Gimme Gimme and Waynetta Slob in The Harry Enfield Show.

The cast is a three-hander, with Roger Lloyd Pack from Only Fools And Horses as senior consultant Dr Robert Smith, Shaun Evans as up-and-coming registrar Bruce and Jimmy Akingbola as the poor patient Christopher.

The action takes place on assessment day, when Christopher is at the end of his 28 days' section and the doctors have to decide whether to release him.

It's a powerful piece of theatre, which is claustrophobic as it is set in a single room with almost no visual features.

Race is a central theme of this play, which also contains strong language as both doctors fight their corner for possession of Christopher's mind.

Lloyd Pack plays a psychiatrist and career man who wants to become a professor at the same time as keeping his job prospects open by keeping to hospital budgets and bed counts. He wants Christopher released at almost any price.

Shaun Evans, as the young psychiatrist, wants to try more expensive and longer treatments, although he quickly understands his career prospects are very much in the hands of his mentor.

This is a play of repressed violence but with a script which is full of superb humour.

Unfortunately, the characters were unengaging and I found it hard to care about their destinies. However, Christopher with his many demons and problems - not least that of seeing all oranges as blue and possibly being the son of an African dictator - does arouse great sympathy.

The script is a beautifully crafted piece of writing, a touch too long perhaps and each of the actors turn in striking performances, not least Lloyd Pack.

The show can be harrowing in parts but would make an ideal play for radio. Burke shows herself to be a canny director at producing black comedy.

Blue/Orange is a sharp piece of theatre which you will love or loathe.