We know what happened in the Holocaust. We know what we think about what happened. And we're wary of playwrights tapping into our responses to these events in their plays: what Peter Hall referred to in his Diaries as "bumming a free ride on the gas chambers". Bravely, two plays open this week that are based on war-time events so terrible they could overwhelm anything the authors have to say.

Both plays deal with the life of a Jewish girl who survives, while members of her family die. Diane Samuels's Kindertransport follows Eva, one of 10,000 unaccompanied Jewish children sent away before the outbreak of the war. We see Eva leaving Germany, arriving in England, growing up there, and then, 40 years later, helping her adult daughter to pack and leave home. The three stages overlap as Samuels divides her central character into the 1940s child and the 1980s adult. As the 1980s mother unpacks cases for her daughter, the two women unpack the mother's hidden past. Three generations of women come into conflict in the one attic.

Former Brideshead star Diana Quick plays Evelyn, the anglicised, emotionally stifled adult version of young Eva (Julia Malewski). Former Bread star Jean Boht plays the humorous, practical mum, Lil, who takes in Eva, and then adopts her. Their accomplished presence - along with a searing performance from Sian Thomas as the mother forced to send her child away - ensures that Kindertransport finds itself playing next door to Sunset Boulevard.

First staged at a fringe venue, the Cockpit in 1993, Kindertransport is an intimate studio piece, using carefully structured, intercutting scenes that combine passages of dialogue (sometimes barely amounting to scenes) with monologues and explicitly plain emotional statements: "Tell me the truth about myself"; "I've never been a good enough daughter"; "Part of me is dead because of you"; and so on.

Close-up, these occasionally incantatory exchanges can be overpowering. Here they look worryingly literal and static. Kindertran- sport has been welcomed - with the enthusiasm normally reserved for sightings of near-extinct species - as a serious play in the West End. The West End doesn't specifically need serious or un-serious plays. It needs West End plays. For all the skilful and sincere arrangement of this heart-wrenching subject matter, this isn't one.

There's a remarkable spell in the middle of Julian Garner's new play at the Hampstead, The Flight into Egypt, when everything unfolds informatively, surprisingly and visually. It's wartime Poland. A taciturn young janitor, Krasinski, excellently played by Con O'Neill, bolts the door of his basement flat, pulls away a panel from the wall and helps a Jewish girl, Beile (Paloma Baeza, making an impressive stage debut), out from her hiding place. O'Neill takes her slop bucket and gives her another. He walks her round and round the kitchen table to relieve her cramp. He gives her a wash-basin. He lies on the bed with his head turned away while she washes and changes. He gives her food and new clothes. Then he helps Baeza back into her hideout and replaces the panel.

O'Neill and Baeza do not exchange a word. In Cracow in 1942 protecting Jews carried the death penalty. The actors draw us into a silent world of dependence and care, where survival depends on the smallest detail. O'Neill and Baeza, directed with considerable nerve by John Dove, catch this tense absorption in an activity that is habitual but fraught with danger. Julian Garner has a talent for depicting character through suspenseful action that develops as we watch. It's all too rare.

The play, which takes place before, during and after the war, takes its title from a 15th-century painting that Ryszard, a Polish academic (Paul Jesson), is restoring. He knocks on the door of Baeza's family home, in search of egg white which he needs for his work. With his prosperous brown pinstripe and readily appreciative manner, he immediately arouses their suspicions. Rightly so.

The 15th-century painting Jesson restores not only shows the Flight into Egypt but also reveals (in the background) the contemporaneous Massacre of the Innocents. Garner adroitly links the parallel of flight and massacre across the centuries, as well as the theme of the redeeming power of art. Thoughtful, tender and engaging, his play creates memorable stage pictures of its own.

There's a delightful Caran D' Ache atmosphere in Adrian Noble's user- friendly production of A Midsummer Night's Dream, which returns to the Barbican, prior to a world tour. It's as if Noble, designer Anthony Ward and lighting designer Chris Parry have unpacked a large box of the expensive Swiss crayons, and decided, to hell with it, let's use the lot. It looks, too, as if most of the production had been sketched in before anyone entered the rehearsal room. Each of the four lovers wears a different coloured outfit (blue, green, orange and purple). Puck and a Fairy descend hanging from green umbrellas. Dozens of large flickering lightbulbs create dappled light on the forest floor; and the upturned pink-cushioned umbrella, the bed in which Titania and Oberon spend the night, is probably on loan from Hugh Hefner. The mechanicals are delineated with cartoon-like clarity. They are a Dad's Army collection, with Flute (Steven O'Neill) definitely taking the Private Pike role.

Director, designer and lighting dominate this attractive Dream. The best performance comes from the huskily regal Amanda Harris, playing Hippolyta and Titania. As the latter she airs her grievance to Oberon (Leigh Lawson) about the stolen Indian boy with a persuasive, all-encompassing argument. Her problem is the world's problem and nothing will be right until it is sorted out. Noble's admirably well-spoken production only slips up when it doesn't trust the material (really, the material's fine).

In the woods, the lovers pinch, slap and head-butt one another. None of this turns out to be half as effective as delivering a line with conviction. They spend too much time running round on their knees. As this crowd-pleasing jolliness spreads across the lovers' quarrels, we worry about the mechanicals' forthcoming production of Pyramus and Thisbe. Sure enough, this entertainment relies more on cute gags than the touching ardour of amateur performers. This smooth-faced bunch hardly match Philostrate's earthy description of them as "hard-handed men". The only horny-handed thing we see them do is labour a joke.

Theatre details: Going Out, page 13.