Ragtime, Piccadilly, London <br></br>Simply Heavenly, Young Vic, London <br></br>The Firework-Maker's Daughter, Crucible, Sheffield

It just ain't got that swing...

Not so much Ragtime as money for old rope. An orchestra, playing everything from piccolo to banjo to double bass, hardly strikes a sincere note all evening in the West End's latest big US import. How on earth did this musical get nominated for 13 Tony Awards on Broadway? Well, I suppose some might be impressed by the self-proclaimed "epic" sweep of EL Doctorow's novel, adapted by Terrence McNally. A saga about turn-of-the-20th-century America, it pointedly embraces the major issue of race relations and other revolutionary movements of that epoch.

Three families from ethnically diverse communities become interconnected. A rich WASP industrialist's wife finds a black baby abandoned in her garden and saves the infant and its mother from the harsh clutches of the law. The baby's father is a pianist who plays the hot new ragtime tunes and wants to be a decent citizen. However, on suffering racist abuse then legal injustices, he turns to violent protest with tragic consequences. More happily, a struggling Jewish-Latvian émigré ends up as a director in the burgeoning film industry and the second husband of the industrialist's wife.

You may learn a little about famous figures of the time, as bit parts include the Russian-born anarchist Emma Goldman and Booker T Washington who peacefully promoted equality via education for his fellow African Americans.

Ragtime's current topicality might strike home too since it deals with xenophobia and terrorism (there's a firework manufacturer who converts to bomb-making).

But oh, the gulf between the issues and the execution. Robert Jones's set is dreary as a bus stop, featuring a few dirty, sheet-glass windows. And the show pumps out sentimentality so shamelessly it's like standing under a gushing sewer of schmaltz. McNally's ill-structured, melodramatic book would be below par for a penny dreadful. The main struggle for Lynn Ahrens' lyrics appears to be fitting the syllables into the lines. Musically, there are some soaring harmonies, with bouts of ululating heartache. And Maria Friedman and her co-stars sing with proficient displays of gusto. But Stephen Flaherty's score sounds like exploitation. Ragtime chords are engulfed in far more clichéd, mainstream slush. American folk tunes are tweaked till they're nauseatingly perky. And the socio-political messages are drummed in as if we're all dunces.

By comparison, Simply Heavenly is a joy. This jazz musical about Harlem in the 1950s was adapted by the Afro-American novelist Langston Hughes from his story, Simple Takes a Wife. A guy called Jesse (gangly Rashan Stone) struggles to make ends meet and can't decide if he wants to settle down or party with his liquor-loving pals. Josette Bushell-Mingo's revival winningly combines a gritty look with slick and buoyant performances.

We become intimate with the regulars at Hopkins' bar because, designed by Rob Howell, it thrusts into the audience with its old cane chairs and worn floor-boards. Instead of a lavish orchestra, we get one upright piano and a wandering guitarist strumming the blues. The plot progresses rather slowly and you feel the cast are straining to be crowd-pleasing comic caricatures. But there are potent flashes of frustration and the romantic subplot is hugely funny with Ruby Turner and Clive Rowe jiving like ecstatic hippos. David Martin's score is swinging, and all the singing is a blast and deftly fine-tuned.

A ludicrously slinky jazz number also sneaks into The Firework-Maker's Daughter. This is the first stage adaptation of the work of award-winning children's novelist, Philip Pullman. The Crucible have collaborated with physical troupe, Told By An Idiot, and the result is delightfully quirky for both adults and children.

Hayley Carmichael, as well as co-directing with Paul Hunter, is charmingly funny and determined as Lila, the girl-heroine of Pullman's (loosely) Siam-set folk tale. Refusing to accept her father's protective brush-off, she sets out to master his craft. Striding off to fetch the required magic sulphur from the grotto of the Fire-Fiend, she scales the walls of the Crucible like a mountain goat. And on returning, she saves her imprisoned father by winning a pyrotechnical competition.

The story's momentum occasionally goes slack and some of the musical numbers are feeble. But Hunter's cool-cat routine as a jungle chef is irresistibly silly. And the company tackle the problem of theatrical fire hazards with lovely inventiveness and tongue-in-cheek wit. Whenever Carmichael wants to light a fuse, an overexcited flame-sprite scurries on, bends over to have a giant match struck on his bottom, then waves red tinsel gloves madly along the flex, making sizzling noises. And Julian Bleach is priceless as the po-faced white elephant, Hamlet – dour as Eeyore, eloquent as Henry James, and slowly swinging along with his haunches fashioned from umbrellas. Worth tracking down.

k.bassett@independent.co.uk

'Ragtime': Piccadilly, London W1 (020 7369 1734), booking to 31 May; 'Simply Heavenly': Young Vic, London SE1 (020 7928 6363), to 12 April; 'The Firework-Maker's Daughter': Crucible, Sheffield (0114 249 6000), to 5 April