Joseph and the Amazing Technicolor Dreamcoat

So, this is where it all began. Andrew Lloyd Webber and Tim Rice, the dream team, wrote their Dream musical more than 50 years ago, the first time the world saw what they had to offer. We hadn’t even made it to the moon when the 15-minute ‘pop cantata’, based on a colourful story from the Old Testament, was written back in 1968.

When Decca recorded an expanded version in 1969 with performances “so ragged” Lloyd Webber was worried they wouldn’t release it, you could still practically count the number of successful British musicals on one hand.

Although their fame bloomed more biblically with their next show Jesus Christ Superstar (also playing in a brilliant version at the Barbican), this quirky romp through musical styles and catchy melodies never went away. In its many forms, Joseph has been a mainstay of British musical theatre ever since.

We’ve experienced Josephs brilliant and terrible, loincloths great and very, very small. We’ve been through David Daltrey, Jason Donovan, Philip Schofield, Donny Osmond, David Cassidy, Darren Day, Lee Mead, Stephen Gately, Gareth Gates, Joe McElderry and H from Steps. And we’re still here.

For its 50th anniversary, producer Michael Harrison has brought Joseph – and Jason Donovan – back to the Palladium for this joyful, colour-saturated production by Laurence Connor. The changes aren’t colossal, but the scale is. Having directed the recent productions of Miss Saigon, Les Misérables, The Phantom of the Opera and School of Rock, it’s a scale Connor is used to. There’s clearly a lot of money behind this, but the show never feels pointlessly flashy.

In fact, it’s a massive blast of joy.

The big change is that the naughty narrator seems to be the one dreaming Joseph into existence, rather than the kids, plus she and her mini-troupe get involved in the action and play a load of the parts from Jacob to Potiphar’s Wife.

That really emphasises what this show is about, and who it was in fact created for: children. Lloyd Webber and Rice wrote it for a school choir. It makes so much sense for children, and for a childlike sense of fun and innocence, to be the driving force. It gives the show a purpose that a lot of other stale productions have failed to find.

At the centre is narrator Sheridan Smith in a glittering tracksuit treating us to two hours of cheeky, perfectly timed comedy. There are so few entertainers like her, and she makes such a massive change from the cloyingly sweet school teacher narrators that have usually corralled the kid chorus in Joseph. Instead, she’s like a naughty babysitter, or some anarchic imp, dreaming up this bright and silly world as she goes along.

She has an amazing ability to make it look like she only half knows what she’s doing, so there’s always a thrilling edge of liveness and spontaneity to the show. She bolts on and off stage as if she’s forgotten stuff and keeps making little winking asides to the audience – and to the performers on stage. She rolls her eyes when Donovan gives it a bit too much, and high-fives a child during a big dance piece.

She belongs on the Palladium stage, like she’s channelling Brucie and Ken Dodd and all those masterful entertainers who’ve been there before.

As narrator, she sits apart from the ridiculous splendour of the production, and occasionally sticks herself into the action by donning a stupid beard (“It’s me,” she grins at us as she pulls the beard aside) or getting stuck into a tap routine.

She and the kids mess about, basically, and that’s what makes the production so special. Everyone on that stage is having an absolute ball and it’s infectious. Even musical director John Rigby is bouncing up and down with abandon.

That glee shines out of Jac Yarrow, too, who beams his way through the part rather than moping around as other Josephs have. Harrison wanted to find a fresh face for Joseph, an undiscovered talent rather than an existing pop sensation, and plucked Yarrow out of drama school.

Despite making his professional debut, he’s so assured and relaxed. He smiles through all of the silliness that the kids inflict on him, like a really patient and fun big brother. He blows Close Every Door out of the park and leads some really tricky – really spectacular – choreography from Joann M Hunter.

Donovan completes the holy trinity as the barely-clothed, arrogantly swaggering Elvis impersonator Pharaoh, but only has one number, Song of the King. In fact, Morgan Large’s set is more of a character than Jason Donovan’s Pharaoh, with big and colourful scenery that Donovan comes on and chews for five glorious minutes.

The design sort of builds from nothing; at the start it’s a couple of sheets hung up by the corners to look like sand dunes. By the interval, we’ve got 10ft tall, gold-plated, guitar-playing sphinxes – the power of the children’s imagination. There are starbursts of rainbow colours, unsubtle and childlike, matching those qualities in Lloyd Webber’s music. Large treats the stage like a playground for the biggest game of dress-up in the world. And obviously there are the costumes – especially a gorgeously intricate dreamcoat.

In pastiching popular musical styles of the time, Lloyd Webber and Rice ended up writing one number as a calypso. Although Connor tries to mitigate the bum-scrunching awkwardness by having a black actor sing it, that very appropriation-y song still sticks in the craw coming from two incredibly posh white men.

Also, Connor really does not know what to do with the women in the ensemble. There’s an equal gender split – great – and a really diverse cast, too – also great – but the men get to play actual characters, while the women have nothing to do except being never fully clothed and dancing sexily.

Aside from those gripes, this is a dream of a production. Go, go, go.

Joseph star Jac Yarrow: ‘If the audience is looking at my loincloth, I’m not doing my job’