Iphigenia in Splott, National Theatre review ★★★★★

Violence and Son (Royal Court Jerwood Upstairs, 2015) was one of the most arresting and affecting plays we saw last year. The deftly written portrait of adolescence made us keen to hear more from playwright Gary Owen. Iphigenia in Splott, his latest play to come to the London stage, has already gathered five star reviews and a 'Best New Play' award from its premiere at the Sherman Cymru Theatre in Wales, and is just as superlative at the National's Temporary Theatre.

Taking its title from Greek drama, the one woman play relocates the mythic heroine Iphigenia to the Cardiff town of Splott. Effie, as she is known, is on a downward spiral of substance abuse and hangovers. Slumping in a grey hoodie, then twitching with hyperactivity, then lashing out at a local mother, she's the epitome of underclass. You'd cross the street to avoid her.

But this is no Vicky Pollard 'chav' stereotype. Sophie Melville's ferocious performance makes Effie impossible to judge dispassionately. With brutal honesty, acerbic humour and generous profanity, she carries you, however unwilling, into her grotty world. Just as you get lost in the depths of the drink-downing and flirting, a one-night-stand with a soldier gives way to sudden, stunning tenderness.

Gary Owen's writing, so intricately intelligent, reels you in then blindsides first with human tragedy, then its political repercussions. You can't help but be devastated as each plot development lurches further from initial expectations. 'Breath-taking' is an overused adage, but during the heart-breaking climax, we didn't actually breathe. Standing ovations are rare, especially on press night, but Sophie Melville had every tear-stained person in the Temporary Theatre on their feet.

This London transfer is the first time a Welsh producing theatre production has been staged at the National Theatre, and it's a shining example of the kind of bold, pertinent new writing that we're coming to expect from The Temporary Theatre under Rufus Norris.