Asif Kapadia’s documentary about Amy Winehouse, whom Tony Bennett describes as ‘one of the truest jazz singers that ever lived’, and who died of alcohol poisoning at 27 (FFS), is masterly and gripping, which is a pity, as you can’t look away. You will want to look away, and may even yearn to do so once the heroin comes into play, and the crack, and that husband and that gig in Belgrade, when she was all unsteady, shuffling and broken beneath the big hair, but you can’t.