Sam Mendes’ Charlie and the Chocolate Factory is a visual feast

That’s the problem with adapting material from an author who relies on the boundlessness of young imaginations; the Willy Wonka factory conjured by scores of Roald Dahl readers takes a rare brand of audaciousness to recreate. Luckily this production has just that, presenting its audience with myriad surprises, from UV raves to Oompa Loompa puppetry that will leave you floating from the theatre doors in a Wonka spell.

Opening with Jack Costello playing young Charlie, the curtain reveals a barren wasteland, at odds with the vast factory looming in the background. Costello owns his role, charming the audience with heaps of stage presence as he longs for the golden ticket that will whisk him into the fascinating world of Wonka.

But one by one we witness the glimmering passports go to a selection of deliciously odious youngsters instead. Played out on the news within a giant television set suspended above the stage, Augustus Gloop’s Bavarian skit and Veruca Salt’s screeching demands remain traditionally Dahl, while Violet Beauregarde and Mike Teavee are given a 21^st century twist, complete with velour tracksuits and fearsome video games that hark back to Tim Burton’s 2005 adaptation.

When Charlie lands the final ticket his grandparents break with convention and stagger from the confines of their four-poster bed to toast his good fortune, before Grandpa Joe – played by the masterful Nigel Planter – escorts him to the factory gates bearing the musical’s first giant ‘W’. As I sat surrounded by 8-year-olds there were gasps as Douglas Hodge’s Willy Wonka emerged from the factory doors, dressed resplendently in pink tails, green trousers and a top hat.

From that moment we were courted by room after room of aesthetic delights, including Dahl’s iconic chocolate waterfall, skewering the centre of the stage and tempting gluttonous Gloop into a vast network of suction tubes. Bad news for Gloop, but a neat opportunity for our first glimpse of Wonka’s taskforce, the mysterious Oompa Loompas, tap-dancing atop his fancy pipework.

Next we paid a visit to the invention room, reimagined with a giant wheel of ingredients and two robots belching out exciting new concoctions, from everlasting gobstoppers to that fated piece of gum. As soon as Violet pops it inside her greedy chops we know what’s coming, but nothing quite prepared me for the rotund purple glitterball she becomes, suspended perilously above the rest of the cast who break into a seventies roller disco below.

Veruca Salt’s dispatchment comes next in a nut room bearing more than a passing resemblance to the set of ITV’s Take Me Out, while Mike Teavee is zapped from view in the futuristic setting of Wonka TV before channel hopping across a series of screens amidst a glow-in-the-dark space rave.

And just when you thought Mendes had overcooked it, concocting an exaggeration beyond even Dahl’s imagination, he reigns it back in. As Charlie and Wonka ascend above the factory – and the audience – in their glass elevator, the stars come out and we hear the beginnings of that familiar melody made famous by Gene Wilder.

The story really finds its heart in these final scenes with Hodge’s wickedly eccentric Wonka striking an emotional chord. The unhinged quirkiness he brings to the role entertains throughout as he pops up around the auditorium, but it's in this moment that he really comes into his own.

The scrumptious set had youngsters gasping and wooping throughout, but there were plenty of laughs reserved for the adults too. Because while this version of Charlie and the Chocolate Factory caters for its young audience, it also makes a point of dropping in jokes for older generations, none better than Iris Roberts’ reinvention of Mrs Teavee as a deranged suburban housewife. “Medication sets us free, one for Mike and two for me,” she trills before pouring a shot of “Mummy water”.

I’m not going to pretend that Roald Dahl would have loved this reworking of his classic story – he famously hated the 1971 film adaptation – but fortunately for Mendes and his team, they don’t have to fear his verbal recriminations. Their show is unashamedly flash with big-budget sets designed to spellbind an audience excitedly awaiting the next big surprise, and while you won't walk out reciting the lyrics or humming the melodies, they neatly bolster a production that makes a character of the factory itself.

Mendes’ cinematic background is clear to see as he paints his vision for the story in animations across giant projection screens throwing back to Quentin Blake’s illustrations – a move that will surely anger theatre traditionalists. But for all its technological pizazz, this is also a musical with a heart that had the audience cheering on their feet by the end. A golden ticket, indeed.