Giant: 'stylishly crafted' Roald Dahl play is 'spectacularly good'

The Royal Court has a monster hit on its hands, with this absorbing, "stylishly crafted" and very timely play, said Clive Davis in The Times . The setting is Buckinghamshire, 1983. Roald Dahl is about to publish his latest children's book, "The Witches". But he's just written a review of a book about the recent Israeli siege of Beirut, in which he crossed the line from criticism of Israeli policy into antisemitism.

Written by the theatre director Mark Rosenblatt, "Giant" imagines a crisis meeting to discuss the fallout, involving Dahl's real-life publisher, Tom Maschler of Jonathan Cape, and Jessie Stone, the fictitious sales director for his US publisher. Both are Jewish. ("She one of your gang?" asks Dahl of Maschler.) Will he agree to issue an apology, or will he seek to brazen it out?

Rosenblatt's debut is "spectacularly good", said Tim Bano in the London Evening Standard – and utterly fearless. It confronts head-on the beloved children's author's " vile antisemitism " while "sweeping along in its ferocious cross-currents of dialogue all the pitched battles of society today: authors with controversial opinions; art versus artist; complicity and silence; the ways we protect the powerful".

But what makes the evening, directed by Nicholas Hytner, really "extraordinary" are the performances. John Lithgow is uncannily good as Dahl: charming, witty and wise, but also restless and irritable. Romola Garai's Jessie holds herself tightly, but there is a "profound dignity to her", especially when "in a quavering voice she defends the Jewish people" from Dahl's "outrageous statements". By contrast, Maschler (Elliot Levey) is "laidback", seemingly bent on appeasing and protecting his author.

Dahl's "bizarre blend of kindness and borderline sadism" is brilliantly conveyed here, said Alice Saville in The Independent . But, ultimately, the play lacks tension, because it's clear from the start that he won't change.

Once the full extent of his bigotry is laid bare, the play doesn't seem to know where to go, said Arifa Akbar in The Guardian . But the journey to that point makes for riveting, brave and intelligent drama. "This is what theatre is for."

Royal Court Theatre, London SW1. Until 16 November