What do you do, in a life-threatening situation, faced with a choice of either keeping your child with you, or sending them away as the only means of ensuring their safety? Most parents would probably swallow hard and say that the survival of the child mattered more than anything. But, according to Diane Samuels, author of a play with this dilemma at its very heart, some children would rather die with their parents than be sent away.

The play, Kindertransport, is a compelling study of the plight of the 10,000 Jewish Kinder (children) sent by their parents to England before the Second World War. First produced in 1993 by the Soho Theatre Company at the Cockpit Theatre in London, winner of awards and recent international success in New York and Los Angeles, the play opened this week at the Vaudeville Theatre in London’s West End. It stars Diana Quick and Jean Boht.

Its heroine, Eva, played by 14-year-old Julia Malewski, is nine when the play begins, learning to sew on buttons in a dingy attic in readiness for her journey to England. Arriving in Manchester, she is taken in by the kindly Lil (later her foster mother), and eagerly prepares for her parents to join her. When they fail to do so, Eva, devastated, attempts to blot out her past, changing her name to Evelyn and becoming more English than the English. Her own daughter, Faith, knows nothing of her mother’s history until, years later, in another dusty attic and in scenes cleverly intercut with those of Eva’s childhood, Faith, too, prepares to leave home.

One reason for the play’s success is that it engages its audience on many levels. “It touches on universal themes,” says artistic director Abigail Morris, who directs the piece. “It is about the Jewish experience and the Kindertransport, but it is also about mothers and daughters, about belonging and separation. When we did the play in New York, I saw black men in the audience weeping.”

But it is a resolutely unsentimental play. The most poignant scenes of parting - including a shocking one when Eva’s real mother, assumed dead, arrives in England and tries to take 17-year-old Eva with her to America - are marked by emotional restraint. “The way I direct it is to let the audience do the crying,” says Abigail Morris. “There is a lot in the play about holding back feelings.”

Rich in its themes, subtle in its structure and patterning, Kindertransport is never inaccessible, but it can mean different things to people of all ages. “So many adults say how complex it is,” says Diane Samuels, writing for the first time for an adult audience, but known for her work for children. “But my sons, who are six and eight, got it completely. Of course, they identified very much with Eva - whereas adults will probably put themselves in the shoes of all the characters at different times. When Eva’s mother comes back, my sons were shocked: they saw her as a malignant ghost.”

Diane Samuels says her own relationship to the play has shifted since she recently lost her own mother. For Abigail Morris, becoming a mother a year ago has intensified her response to certain aspects of the play. “Some of the simplest lines I find very moving - such as when Eva asks to stay up on her last night at home, and her mother says: ‘We will carry on as we always do. Bedtime is bedtime.’ Now I understand the sacrifice that mother is making in sending her child away. There is that urge at bedtime - that so many parents felt on the day of the Dunblane tragedy - to hold your child a little bit longer, a little bit tighter.”

For Julia Malewski, who plays Eva at nine, 15 and 17, the saddest point in the play comes close to the end when Evelyn says, as though to her mother, “Didn’t it ever occur to you that I might have wanted to die with you? Because I did. I never wanted to live without you and you made me.”

“It makes me think how lucky I am not to have had to go through that,” says Julia, and she explains what 17-year-old Eva feels when her mother reappears: “At first I don’t want to let her near me, but at the same time I want to reach out to her. I’m thinking: ‘You left me, so why should I forgive you straightaway and go with you’ - though part of me wants to do just that. ”

“Outstandingly assured” was how the Guardian’s theatre critic Michael Billington described Julia Malewski’s performance in the Watford production. Off stage, in jeans and navy V-neck, eating chips during a rehearsal break, her assurance is tempered by diffidence when talking about herself. But she admits to finding it “quite hard to play a nine-year-old - I can’t remember what it was like, but I’ve got a cousin who is nine, which helps”. As a 17-year-old, “I just try to act grown up - I move very upright and proper.”

Apart from small parts in school plays and a voiceover for the BBC’s Junior Big Break, Kindertransport is Julia Malewski’s first real taste of the stage. “I wouldn’t say it’s glamorous - it’s hard work. But it’s fun, and the other actors are really nice to work with. My friends think it’s brilliant.” Her ambitions do not yet extend beyond GCSE drama, which she will take in two years’ time at St Bernard’s Convent in Slough, and possibly English for A-level.

Ursula, her mother, now her part-time chaperone, is taking the theatre in her stride, confident that it is not affecting Julia’s school work, “as she is a pretty good student, and good at catching up”. Ursula Malewski loves the play and believes it has much to offer 12- and 13-year-olds studying the Second World War. School parties from the Watford area saw Kindertransport earlier this year, and London schools now have the same chance. “Seeing the play is something they can be part of,” Ursula Malewski says. “Being able to relate the trauma of the Holocaust to one child makes it much more real.”

Vaudeville Theatre box office: 0171 836 9987.