Shock Treatment, The King’s Head Theatre

I’m suspicious of sequels. And prequels. Any attempt, really, to spin out a film’s appeal for more bucks – often to the eternal damage of the adoration nurtured for the original – sets my teeth on edge. Let’s call it the Phantom Menace effect.

So while I’m a big fan of The Rocky Horror Picture Show, I’d never seen Shock Treatment, its much maligned 1981 follow-up. For a start, what could top Tim Curry in fishnets? But maybe I was wrong to avoid this cult offering from Richard Crystal Maze O’Brien (warning: click on that link at your own procrastinating peril). Shrunk down and tarted up at the tiny King’s Head Theatre, with a newly adapted (and apparently more coherent) book from Tom Crowley, Shock Treatment is a jolt (sorry) of ridiculous, kitschy joy.

There’s no Frank N. Furter (boo), but Brad and Janet are back in this sequel, now (un)happily married and living in a suburban landscape of picket fences and anti-depressants. Denton is a waking nightmare of toothy grins and repressed desires, as well as being at the forefront of a now eerily prescient experiment in embryonic reality TV. So instead of working out their marital problems at home, Brad and Janet are dragged in front of the cameras, where they soon fall prey to the exploitation and aspirational hokum of the mass media.

Looked at now, the satire – if a little wonky – is astonishingly ahead of its time. When we arrive, Denton has fallen under the sway of Farley Flavours, a larger-than-life media mogul who uses the town’s television network as an advertising platform for the many other pies he has fingers in. In Brad and Janet, he sees an opportunity to up the ante – and the viewing numbers. Handed over to creepy brother-and-sister doctor duo Cosmo and Nation McKinley, Janet undergoes an X-Factor style makeover, while her unfortunate spouse prepares to fry for the sake of ratings.

The plot still isn’t entirely watertight, but then the appeal of Rocky Horror was never exactly its narrative prowess. Instead, what charms about Shock Treatment is the unapologetic kitsch, the facial acrobatics of the performances, the slightly-shit-but-owning-it quality of the whole gloriously tacky endeavour. Squeezed onto the snug stage of the King’s Head, the action of Benji Sperring’s production is confined to Denton’s television studio, a sterilised world of dazzling white against which the TV stars’ neon outfits and inane smiles are all the more lurid. The aesthetic is Stepford Wives suburbia meets reality television excess.

And it’s the sharp precision of the style – swapping B-movie schlock-horror for uncanny small screen sheen – that lets Shock Treatment hold its own alongside Rocky Horror, if never quite matching up to it. There’s more than a hint of Riff Raff and Magenta to the Doctors McKinley, given just the right edge of the surreal by Nic Lamont and Adam Rhys-Davies, while Mateo Oxley’s closeted TV host Ralph Hapschatt has perfected the stretched grin of the would-be celebrity. Julie Atherton, meanwhile, is brilliant as ever in the role of easily duped Janet, taking to new found fame with just a tad too much relish. Plus, there’s a score of murderously catchy tunes, including the Time Warp-esque “Little Black Dress” – complete (naturally) with dance moves.

It is, oddly, as though Shock Treatment has suddenly found its time. Back in the early eighties, over a decade before The Truman Show, the film’s vision of real lives played out on screen must have seemed as outlandish as the outfits. Now, as Celebrity Big Brother stubbornly trundles on and media giants like Rupert Murdoch tighten their grip on every aspect of our lives, O’Brien’s concept looks chillingly prophetic. Sophisticated social critique it ain’t, but beneath the songs and jokes and slapped on smiles, there’s something altogether more sinister.