Eric goes from Clapton to clapped out and back again in this new documentary about one of the world’s greatest blues guitarists.

A Life in 12 Bars is directed by Lili Fini Zanuck, her first feature as director since 1991’s Rush, for which Clapton did the music. Here he lends his extensive archives, home movies and some commentary to a detailed but overlong account that feels more like A Life in 12 Hours.

From the early revelation that the woman he thought was his mother was in fact his grandmother, to the tragic death of his young son in 1991, via addictions to heroin and then alcohol, Clapton’s story is infamously sad. This makes for one of the more depressing rock docs I’ve seen.

It starts with an excited foray into blues and ’60s music, including some fantastic footage involving Aretha Franklin and Muddy Waters, before getting bogged down in the details of the gloomy love triangle between Clapton, his best friend George Harrison and Harrison’s wife Pattie Boyd.

The film attributes Clapton’s pursuit of his best friend’s wife to his mother’s rejection of him, while his notorious pro-Enoch Powell rant is put down to drunkenness, conveniently forgetting that he has doubled down on those comments on several occasions in sobriety.

Clapton denounces his fascistic (his word) and Morrisseyming (my word) behaviour, and he’s been through the wringer like few have, but this film actually left me liking him less than when I went in. I always took the famous “Clapton is God” graffiti as a nod to his ability, but it could equally refer to his nastiness.

Although it (or possibly he) lacks the personality of Beware of Mr. Baker, the memorable profile of his Cream bandmate, the documentary does make a case for the strength of music as an escape from the darkness of an unhappy life. In the end Clapton, like Sam Worthington in Avatar, was saved by the blues.