Samuel and Timothy West in A Number at Fugard Theatre.

A NUMBER. Directed by Jonathan Munby, with Timothy West and Samuel West. At the Fugard Theatre until October 29. TYRONE AUGUST reviews.

WHEN Dolly the sheep was born in Scotland in the late 1990s, it unleashed a new wave of questions about the ethics of human cloning. Dolly was, of course, the first mammal in the world to be cloned from the cell of an adult.

It was in the wake of the debates raging at the time that the British playwright Caryl Churchill wrote the play A Number.

The central characters are a father (Timothy West) and his son (Samuel West). But all is not what it seems. The son, Bernard 2, is in fact a clone.

We are subsequently introduced to the first son (Bernard 1, also portrayed by Samuel West). He is a rather menacing character who is furious when he discovers that there are clones of him.

The father and son are clearly estranged: Salter, we are told, was not the most attentive and loving father. In a vain and self-centred attempt to redeem himself, it appears, he decided to give fatherhood another go – not with another child but with a genetically identical version of his son.

“I wanted you again,” he tries to explain to his son. “You were the most beautiful boy.”

Salter lies, telling Bernard 2 that he was cloned after the death of his mother in a car crash, and threatens to take legal action against those who cloned more than one version of him.

“They stole your genetic material,” a seemingly outraged Salter tells him.

However, Salter may not be an entirely innocent victim of unscrupulous doctors. Churchill hints at motives of financial gain (there are suggestions that there may be as many as 19 clones of Bernard 1).

However, the playwright’s primary concern seems not so much the ethics of human cloning, but rather its possible consequences.

Bernard 2’s very sense of self is destroyed. “I feel terrible,” he tells his father.

Salter’s response is far more pragmatic: the clones are all still people, he believes, who just happen to be identical.

These contesting notions of self and individual identity are at the very heart of the play.

Another key theme is the perennial nature-versus-nurture debate: whether genetics or the environment is the primary factor that shapes the character of a person.

For Churchill, it seems, the environment is the most important influence: Bernard 2 is far more mild-mannered and stable than the first son.

This is signalled even more clearly by the experience of the second clone, Michael Black (Samuel West again), who grew up in the home of another family.

He appears to be quite well-rounded, even to the extent that he is amused by the discovery that he is a clone.

“I think it’s funny,” he tells a bemused Salter. “I think it’s delightful.”

But this is no all’s-well-that-ends-well tale. Bernard 1 tracks down Bernard 2 and kills him.

This can either be seen as an anguished act of jealousy or a perverse attempt to regain his sense of self and individuality.

When Salter hears this, he shows genuine remorse for the first time. “It wasn’t his fault,” he tells Bernard 1.

“You should have killed me.”

This is a sparsely written and demanding play: the dialogue requires close attention, both for the rhythm of the language and to follow which of the sons is on stage with Salter.

(Samuel West helps to delineate the characters by employing different accents and mannerisms.)

The result, though, is rather curious: on the one hand, A Number appears to point to the destructive potential of human cloning (Bernard 2’s murder); on the other it presents human cloning as potentially benign (Michael Black’s casual acceptance of his status).

The play closes on this open-ended note. Of course, like all artists, playwrights are not in the business of providing answers but of asking questions.

Even so, the play does end a bit up in the air (no less because of Salter’s less than charitable motives for cloning his son).

Nevertheless, it is a provocative and stimulating work, in terms of content and form and is a powerful indication of why Churchill is held in such high regard.

This production is first-class theatre: an outstanding real-life father-and-son cast are supported by Jonathan Munby, a supremely talented director.

Hartley TA Kemp’s lighting design – the display of glass test tubes above the stage is a sheer touch of brilliance – adds to the feast for the senses.

A Number is a most engaging and entertaining play.

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