You could probably choose a less conspicuous method of defecting than floating across the border in what looks like a giant glowing lightbulb. Yet a spectacular nocturnal breakout from communist East Germany by hot-air balloon is exactly what two families did in September 1979 – the basis of this glossy mainstream thriller released in Germany for last year’s reunification anniversary. Sadly, director Michael Bully Herbig – a well-known German comedy star – does them no favours with a frantic shooting style that somehow manages to render this terrifying endeavour both bombastic and trivial.

Friedrich Mücke and Karoline Schuch play the Strezlks, a disaffected electrician and his wife who, desiring an unfettered future for their two sons, decide to Montgolfier it out of the GDR. When a northerly wind rears up, they break out the balloon they have painstakingly constructed with their friends the Kretzels, before realising that it will hold only one family. The Strezlks go it alone, but their jerrybuilt rig fails them at 1,800 metres, leaving them short of the west and back to square one.

Herbig directs every scene with an overcranked mania, accompanied by a blaring Zimmer-esque score that thinks it’s part of the buildup to a Navy Seals assault on an Indian Ocean pirate ship. The longer Balloon goes on, the more this exposes the script’s thinness and a reliance on manipulative reversals to cattle-prod tension upwards. There’s little political context, beyond comedy Stasi neighbours waving from over the street. Even Thomas Kretschmann, initially imposing himself as the phlegmatic apparatchik leading the hunt for the would-be balloonists, is wasted.

How Herbig fails to capitalise on the sheer physical terror of their flight – the balloon’s basket is more a flimsily strung boxing ring – makes you wish someone like Werner Herzog had mounted this mad escapade for real.