Musical misfits embark on a frankly absurd adventure

In the mid-1980s, musician Chris Sievey gave birth to Frank Sidebottom, a sharp-suited comic persona with a large papier-mache head, who was forever 35 years old and carried a hand-puppet sidekick named Little Frank.

This cartoonish alter-ego became ensconced in the Madchester music scene, made regular appearances on television and famously gave birth to Caroline Aherne’s mock talk show host Mrs Merton on one of his radio shows.

Having faded into relative obscurity in the 1990s, Sidebottom made a series of comebacks and remained a cult favourite on the music and comedy scenes until Sievey’s death in June 2010.

Journalist Jon Ronson’s memories of the man and the myth provide an unlikely spark of inspiration for Frank, a musical comedy that is, to be frank, too self-consciously bonkers for its own good.

Ronson’s script, co-written by Peter Straughan, taps into the appeal of other outsider musicians like Daniel Johnston and Captain Beefheart as it dramatises the efforts of a group of misfits to record an album.

Oscar nominee Michael Fassbender, who was terrifying in 12 Years A Slave, spends almost the entire film encased within a giant fibreglass noggin, concealing his emotions from us as well as the rest of the cast.

The unlikely narrator, though, is Jon (Gleeson), a musically-challenged, socially awkward young man, who composes lyrics in his bedroom.

During a walk along the beachfront, he encounters a band called the Soronprfbs, whose keyboardist has just suffered a mental breakdown.

“Can you play, C, F and G?” asks the band’s manager Don (McNairy) and Jon is hastily enlisted to play a gig that night where he must gel seamlessly with theremin player Clara (Gyllenhaal), French bassist Baraque (Civil), percussionist Nana (Azar) and quixotic lead singer Frank (Fassbender).

The concert is a disaster, but Jon keeps his place and joins the band on a rural Irish retreat to record an album.

In this idyll, Jon discovers that Frank plays with madness every day and demands unachievable perfection from the band, “Frank is, with all his issues, the 100 per cent sanest cat I’ve ever met,” coos Don.

There are undeniable moments of fiery brilliance, including a sexually-charged encounter between Jon and Clara in a hot tub.

But these cannot compensate for the lunacy that Frank wears like a badge of honour. Every member of the band is dysfunctional to the point that we struggle to relate to them.

“I used to have sex with mannequins. It’s a condition,” casually confesses Don, one of the more down-to-earth members of the crazed circus.

Gyllenhaal sinks her pearly whites into her role with gusto, but Gleeson’s delusions of musical grandeur wear thin well before the Soronprfbs embark on an ill-fated trip to Texas to perform at the South by Southwest music festival.