There is a huge range of subject matters available for a good documentary. The best to my mind are those that showcase something very real, but which you would be unlikely to believe unless someone had spend years putting together a documentary about them. That is certainly the case with Chris Sievey, an aspiring pop musician who turned to comedy and became a northern English folk hero when he put on a spherical papier mache mask as the childlike Frank Sidebottom.

For a while during the 1980s Frank was everywhere. Live concerts, children’s television, comic strips, even his own aggressively weird comedy talk show. The character was adapted loosely into Lenny Abrahamson’s 2014 feature film Frank. Describing Frank Sidebottom is rather difficult. Ultimately it is best to simply load up some video clips from YouTube and experiencing him for yourself. He is regularly less funny for actual jokes, and more for simply being very odd. There’s the personality and weird voice, the papier mache head, the puppets, and the rather charming love for Gerry Anderson’s Thunderbirds. It all builds to form a peculiar and divisive comedy figure, not to mention tremendous material for a feature documentary.

Director Steve Sullivan tells a fairly traditional biographical documentary, combining talking head interviews with a huge amount of archival footage to tell the story of Chris Sievey from childhood to his untimely death in 2010. Sullivan is clearly an ardent fan of both Sievey and his masked alter-ego, but it is to his enormous credit that he does not descend to hagiography. Sievey is presented as a deeply flawed individual, one suffering from depression and what appears to be a growing mental illness. He suffered through alcoholism and crippling personal debt. Contrasted with his deliberately breezy and absurd performances as Frank, it all presents a complex and fascinating picture.

The most significant aspect that the film impresses on its viewers is Sievey’s creativity and dogged persistence. When he and his brother failed to score a record deal for their pop music, Sievey simply started recording and selling tapes himself. When he grew interested in home computers in the early 1980s, he attached three short programs to the b-side of a single he had recorded. When the comic magazine Oink! enquired about producing a Frank Sidebottom comic strip, Sievey wrote and illustrated it himself. Sullivan does an exceptional job of showcasing the unexpectedly broad range of Sievey’s talents, as well as the varied success (or lack of it) that each stage enjoyed.

Pre-existing fans of Frank Sidebottom will clearly find the most value here, as the film unashamedly celebrates Sievey’s creation and comes soaked in rare performance footage. Viewers entirely new to the cult of Sidebottom may come away enchanted, but they could just as easily emerge disinterested. Given the deliberately naive and archaic tone of the character, he can be rather divisive. Whatever way you lean when watching it, he’s an unusual enough figure to make for excellent documentary material. Personally, I think it’s all rather delightful.