A man lies dead in a bathtub in a Bristol flat, David Bowie’s ‘Heroes’ playing on the radio. His brother sets off from London in a battered Rover to find out what happened. He doesn’t. And neither do we, for that matter.

Not, perhaps, the most compelling of pitches (I’d like to see this get past the Film Council these days), but rookie director Chris Petit (Time Out’s film editor during much of the Seventies) was by his own admission completely uninterested in, and ill-equipped to deal with, such cinematic staples as plot, narrative development or psychology. If Hitchock’s actors were cattle, Petit’s are lab rats, trapped in a maze they have no understanding of and no way of escaping; or they’re figures in a landscape, placed there to anchor the eye and draw us into one of the strangest pictures of Britain ever put on screen. Much of the fashionable angst and alienation can be put down to the European influence of Godard, Antonioni and, more notably, the New German Cinema, particularly the work of Wim Wenders – whose road movies are an overwhelming influence and whose Road Movies co-produced Petit’s film.

So, what is Petit interested in? Architecture, landscape, weather, cars and music. The architecture tends towards Sixties tower blocks and decaying modernism-lite hotels, as well as that of the motorway system itself (this is a road movie, after all), with its junctions, roundabouts and flyovers. But this black and white urban landscape – especially that of the outskirts of London – is more JG Ballard than Ken Loach, more Out of the Past than Room at the Top, a space not for dramas of social realism or ‘housing problems’ but for the noirish imagin­ation, paranoid or otherwise, to drift. And, more than anything, rather uniquely in a traditionally talky British cinema, this is just the backdrop for a soundscape. It’s the stuff that unrolls through your windscreen as the car stereo plays – Berlin-era Bowie, Kraftwerk and a job-lot of Stiff artists like Lene Lovich and Wreckless Eric: these are the images to the soundtrack of your life, the accompaniment to the compilation tape you put together with such a journey in mind. Yes, it’s arse-backwards film-making, in which the images gain their resonance from the music of the real world, but it’s also something we all now understand in a world of atomised iPodders, each starring in their own private movie.

Ultimately, then, it’s about Sound and Vision, about cinema – and specifically British cinema – caught drifting, as ever, somewhere between Europe and America. Yes, it’s irritating at times – a compendium of ‘film culture’ concerns that never extended far beyond the BFI or the dreary pages of Screen during its Marxist-feminist heyday. But it’s liberating too – as free of stodgy exposition and pop-psychology as it is of human warmth or humour – like any aimless car journey, even one as delimited as this is by the confines of this tight little island. Petit later found a kindred spirit in the shape of writer and psychogeographer Iain Sinclair, but this debut effort has a freshness and shock-of-the-new that these later collaborations lack. Ultimately, Radio On seemed like a dead end: its only progeny came much later, in the very different form of Patrick Keillor’s films, like London and Robinson in Space, and its commitment to just drifting (or just driving) was never going to catch on in a cinema as addicted to the pleasures of problem and resolution as is our own watered-down wanabee Hollywood – or, indeed, in a country where the most iconic road we can offer to compete with Route 66 is the M25.