Some documentaries draw their power solely from their subject. The story of Fela Kuti, leader of the band Africa 70, pioneer of Afrobeat, anti-corruption activist and one-time husband to 27 women, has enough juice to jump-start a festival's worth.

The Nigerian folk hero's charisma carries Alex Gibney's film. As with much of Gibney's recent work, Finding Fela! is well-researched, snappily edited and largely inessential. Gibney pegs his film to the making of Fela!, a hyperactive Broadway musical based on Kuti's life and work. There's an exorbitant amount of screen time given to backstage hand-wringing about how to bring the legend to life, with the film at times bordering on advertorial for the stage show.

Kuti made politics to dance to, and music that made you think. The slick presentation of Gibney's film successfully gets that appeal across, but the method feels compromised. Finding Fela! seems mapped out in a theatre on Broadway, stuffed with contemporaries and acolytes (Tony Allen, Paul McCartney, Questlove) willing to laud the man's talent, pay tribute to his politics and, unfortunately, incite us to see Fela!

• This article was amended on 5 September to replace a picture incorrectly identified as Fela Kuti.