****

Finally they find it, lurking at the bottom of a heap of unsolicited scripts: a diabolical gem that radiates bad taste.

"It's practically a love letter to Hitler," marvels Max Bialystock, Broadway's most consistently unsuccessful producer, holding a script guaranteed to flop and – through some creative accounting – make him a fortune.

Mel Brooks’s 2001 musical, adapted from his 1968 film, is a giddy celebration of cynicism, ambition, exploitation and showbiz: it’s practically a love letter to Broadway.

This spirited touring production is a comparable feat of shrewd business, led by celebrity performances, but it’s also attuned to Brooks’s deeper affection for musical culture. In sending up Broadway, Brooks scatters a trail of references to its ritzy past with a humour that is part satirist, part schoolboy.

If anything, it's the brimming, beaming innocence of the show that makes it all so palatable. Director Matthew White zips his ensemble through its paces, daubing Brooks's already allusive tunes with a further jingle of references: Fiddler on the Roof, Show Boat, Top Hat, flashes of Liberace and Ethel Merman.

For all the schlocky standards of Springtime for Hitler, Brooks's musical within the musical, such gestures recognise that our show must be something slicker.

This production, designed by Paul Farnsworth, is economical without skimping on the details. The famous highlights of the original staging – sieg heil-ing pigeons and a rotating swastika of chorus girls – find more modest equivalents here, demanding more ingenuity from the cast.

The star names acquit themselves admirably: comedian Jason Manford, a heavier-set Leo Bloom (the accountant nebbish with delusions of razzmatazz) is gamely at home performing hysteria amid song- and-dance numbers. Ross Noble is reliably mad-eyed as the hilariously deranged Nazi playwright.

But it's Cory English, as Max, who is the star of the show by a considerable distance. A rotund bundle of energy, English grants this gerontophile Lothario the show's most sustained physical performance, by turns hilariously exasperated and exhausted, and – in the show's stand-out moment – delivering a bravura recap of the entire performance. Tiffany Graves is fun as well as Ulla, an unreconstructed Swedish bombshell, who finds the right balance between coquettishness and knowingness.

Oddly, it isn't the comedy of A Gay Romp with Eva and Adolf at Berchtesgaden that now smacks of poor taste, but Brooks's unbridled nostalgia for a time before political correctness. Every gay man here is flaming, every chorus girl a confection of spangles and exposed thighs, every German a closet Nazi.

You'd dismiss it if it wasn't so well executed, so full of good will, so compulsively fun. The achievement of The Producers, on every level, is that it gives us ebullient permission to laugh at anything. Until July 11th