Julien Temple originally expected to cover the last months of Johnson's life after he'd been diagnosed with terminal cancer. But that changed after photographer, fan and surgeon Charlie Chan persuaded the ex Dr Feelgood man to seek a second opinion - leading to the operation that saved him.

Temple tells the BBC: "It was about two months between my coming on board, and suddenly Wilko getting his amazing news. My mum was dying at the time that Wilko was so ill, and all the emotions began to emerge. I actually found what Wilko said, both on and off the screen, very inspiring."