Closer to Heaven (Union Theatre)

At the time, Mamma Mia! was two years old and every British band ever – Queen, Madness, Boney M – was rearranging its back catalogue into some sort of storyline. Somewhere, I imagine, a producer had hooked up Vera Lynn and David Hare for a brainstorming session: There'll Always Be An England – a State of the Nation Musical. Such was the gold rush of the jukebox musical.

So it's to their credit that the Pet Shop Boys, ever innovative, did something different. Closer to Heaven folds in a couple of their lesser known tracks – "Shameless", "In Denial" and "Vampires" – but most were written specially. It makes for a pretty decent clubby score that refreshes the traditional musical without sacrificing stylistic consistency like the mix-tape approach. It certainly passes the earworm test – "My Night" and the title track, in particular – though partly because it's so insistent in its call-backs.

'The plot's stringier than the dancing boys' vests'

The problem has always been Jonathan Harvey's lame-ass book. It's Hollyoaks bad. Hell, it's Family Affairs bad. It's every coming out story ever, as 'Straight Dave' (Jared Thompson) overcomes his Catholic guilt and opens up to his bixsexuality, falling for a working-class cliché, drug dealer Mile End Lee (Connor Brabyn). He's landed in London and got a job at a gay club, dancing with its faded star Billie Tricks (Katie Meller), a dried-out, drug-addled dah-ling of the club scene, while initially dating the boss's daughter Shell (Amy Matthews).

From there, it's also every drugs-are-bad-kids and every perils-of-fame narrative ever written. Lee stares at his hands before suffering an overdose. Dave gets exploited by a cowboy pop producer Bob Saunders (Ken Christiansen). None of the sub-plots quite add up and they certainly don't hang together. The whole piece starts with an estranged father and daughter reunited – only to make nothing of that particular relationship. He turns to drugs. She's disappointed. It's hard to believe that this is the same Jonathan Harvey who wrote Beautiful Thing. The plot's stringier than the dancing boys' vests.

An all-out production might just gloss over these loose ends. Gene David Kirk's, for all its fresh-faces and hairless chests, isn't it. In the no-frills railway arch of the Union, Vic's club looks like the sort of place best left to its regulars, where sweat drips down the walls and your shoes stick to the floor. David Shields' design goes for fabulous but, with a few feathers and the odd strip of mirror, comes up cheap and nasty. Closer to Heaven, maybe, but a long way from Fabric.

As always in this compact space, there's pleasure in close-up choreography and Philip Joel's routines are explosive, if insistent in their raunch. The acting's not quite tongue-in-cheek enough to surf the shonky dialogue, nor low-key enough to find its truth. The exception is Brabyn's matter-of-fact Lee, while Thompson is likeable, if trying too hard. Meller is spirited as the has-been Billie, puncturing through with the wistful number "Friendly Fire", and Matthews has a big old belt voice. None of that, however, justifies giving this duff musical an afterlife.

Closer to Heaven runs at the Union Theatre until 23 May 2015