David Walliams is conquering British culture sector by sector. After sketch comedy, TV panel shows and marathon charity swims, he almost inadvertently became one of the country’s most popular children’s authors; in the last couple of years, stage adaptations of his books have become nearly as ubiquitous in school holiday time as those of Roald Dahl or Julia Donaldson. He seems instinctively to blend the mild transgressiveness of Dahl with a dollop of his own trademark campery yet follows an affirmative sentimental vector of the kind that gives both children and adults a warm glow.

His 2010 book portrays 12-year-old Joe (or, in this version, Jo) Spud, immensely wealthy as a result of his father’s invention of wet/dry BumFresh toilet roll; Jo wants to be an ordinary boy at the local comprehensive school, but his money keeps getting in the way whether he hides it or flashes it about, and is particularly toxic to true friendship. Walliams blends his old-fashioned “money can’t buy you happiness” theme with gasp-and-giggle material such as purple bottoms, inventively disgusting school meals and Jo’s dad’s forlorn, ridiculous succession of wigs. It hardly sounds like the stuff of musicals, but then nor did Charlie And The Chocolate Factory.

Songwriters Miranda Cooper and Nick Coler have a couple of decades’ experience in the pop/rock arena, composing or producing for a range of artists from Franz Ferdinand to Girls Aloud. That gives you a fair idea of the musical idiom here: generally upbeat, seldom all that demanding. It is, I suspect, co-lyricist and adapter Jon Brittain who adds the sparkier stuff. This is not simply a matter of smart turns of phrase; Brittain deconstructs the show itself as he goes along, with numbers dedicated to the function of opening the second half and tying matters up in an epilogue, characters tripping up their storylines and of course the old “stopping just short of a really filthy rhyme” ploy.

If this sounds a bit knowing for a family show, it’s not that much more than your standard panto does these days. True, some of the gags go over the children’s heads, but my reservations on this score were largely dispelled when I heard a peal of youthful laughter at a joke about Piers Morgan. Director Luke Sheppard infuses an easy, matey panto spirit into his company of ten. Dean Nolan doubles as Jo’s dad and a dame-like school dinner lady (a role taken by Walliams himself in the 2016 BBC TV adaptation), and Avita Jay switches between dad’s gold-digging girlfriend and a newsagent/confectioner who acts as a kind of Buttons/Wishee Washee audience’s-chum figure.

Ryan Heenan’s Jo isn’t the most charismatic of leads, and the actors don’t always hit their notes spot on, but it doesn’t really matter. This isn’t a glittering blockbuster, it’s a holiday-time cavort. And, as one of the recently demised Nicolas Roeg’s film characters remarks, I like a bit of a cavort.

Written for the Financial Times.