The very talented actor and musician Johnny Flynn here makes a perfectly game attempt to impersonate the young David Bowie in this ironised and fictionalised account of Bowie’s 1971 US publicity tour which – partly – inspired his Ziggy Stardust persona. Flynn carries off Bowie’s clothes and delicate mannerisms plausibly enough and, impressively, he does his own singing. But, all too often, this Bowie looks as if he is presenting TV’s Bake Off.

Bowie arrived at Washington DC’s Dulles airport where an immigration official called him a “fag”, and where Mercury Records publicity man Ron Oberman (played here by comic Marc Maron) arrived to meet him, having got a lift to the airport from his mum and dad, and took the bemused Bowie back for a home-cooked family meal, like a 13-year-old foreign exchange student. The movie shows this, but where in reality the tour saw Bowie fly to major cities, meeting with Oberman a few times and doing interviews, the movie escalates this to a huge comedy-odd-couple road trip. Oberman and Bowie head across the country in Ron’s uncool, un-rock’n’roll station wagon, with Bowie playing disastrous, low-key gigs and Ron becoming a Spinal Tap-type PR goof who is mortified at the poor turnout.

Meanwhile, back in London, Jena Malone plays the heavily pregnant Angie Bowie, who comes across as a charmlessly shrill and bad-tempered scold, and David is having traumatised flashback memories of his troubled brother Terry (Derek Moran). The movie makes a laboured connection between Terry’s mental illness and David’s dark imaginings, a connection that surely comes close to misunderstanding the nature of schizophrenia. And so the tour goes on, and Bowie providentially hears (or hears about) the music of Iggy Pop and cult psychobilly star Legendary Stardust Cowboy, which fed into the Ziggy Stardust creation.

This is a strained, frustrating concoction that doesn’t do its subject justice. Flynn really can sing, though.

• Stardust is available from 15 January on digital platforms.