He’s waved his wand on screen as Harry Potter, whipped off his clothes on stage as a troubled teen in Equus and now Daniel Radcliffe has adopted an Irish accent, a hobbling gait and a mangled arm as Billy, the eponymous youth who lives with his adoptive “aunties” on an isolated Aran isle and dreams of escape.

Set in 1934, Martin McDonagh’s 1990s black comedy mixes fiction with an element of fact (an American film crew really did descend on the area to make the documentary Man of Aran) but the characters are his own.

Pat Shortt’s grubby Johnnypateenmike splits his time between delivering  (usually very tedious) local gossip and trying to kill off his frustratingly resilient old mother (June Watson) with forbidden bottles of illegally brewed booze.

The aunts (who run the local store stocked almost entirely with stacks of canned peas) have their own peculiar habits – Ingrid Craigie’s fretting Kate talks to stones at times of stress whilst Gillian Hanna’s down-to-earth Eileen eats the sweets before the customers can even sample them.

With nothing to do to pass the time, Radcliffe’s Cripple Billy (there’s nothing politically correct about McDonagh’s work or the locals he portrays) has turned to books and staring at the cows – but he’s determined to grab the chance of a screen test on a neighbouring island.

It’s an effectively understated performance which contrasts well with Sarah Greene’s abrasive Slippy Helen, a foul-mouthed little minx with a penchant for cracking eggs over all and sundry.

There’s more than a touch of pastiche about London born and raised McDonagh’s writing, but his dialogue fizzes with cruelly funny brio and, fully acknowledging this, Michael Grandage’s snappy production makes you laugh even when you know you shouldn’t.

Noel Coward, St. Martin’s Lane, WC2N 4AU
Tube| Leicester Square
Until 31st August
£10.00 – £57.50