This is a long book, and a wildly entertaining one, but four of its most revealing words come before it starts, in Mick Wall’s dedication. It reads simply, ‘To Axl, you won’. This captures Wall’s grand theme, implied too by his title, that Guns N’ Roses are the last great rock band created by a music industry model that no longer exists, and living the kind of throwback lifestyle that will appall and terrify any snowflake millennial that dares to crack the spine and enter a vanished world.

But it has another meaning, too, something that sets Wall’s writing on Guns N’ Roses apart. He has reported since the start: his first book on them, a collection of his early Kerrang! interviews called Guns N’ Roses: The Most Dangerous Band In the World, is a kind of founding document for Last Of The Giants, and demonstrates how close he was as they took off – Axl would summon him late at night to talk, drink and often rant about whatever was in his head. By the time the band played at Rock In Rio in 1991, the creeping, druggy paranoia that was taking hold saw him ostracised, and then came Get In The Ring, a song on Use Your Illusion II that named him and inadvertently, as he writes, made him even more famous.

There is a lot more to that story, and it forms a subtext to the second half of the book, as Wall considers his relationship with a man who becomes a kind of mythic rock’n’roll construct as he disappears for a decade to make and remake one of the weirdest and baroque albums ever, the glittering edifice to superstar indulgence that is Chinese Democracy.

Last Of The Giants is absorbing, sometimes dizzyingly so, because Wall hasn’t relied purely on his early access. Two of its stars are Alan Niven and Doug Goldstein, the feuding former managers of the band (Niven initially employed Goldstein as Guns’ tour manager before Goldstein – depending on whose version you believe – finagled his way into Axl’s affections and engineered Niven’s sacking). Both are wonderfully vivid interviewees, and their contrasting methods of handling the essentially unmanageable Axl Rose form a jaw-dropping Rock’n’Roll Life Class 101.

A novelist could not have produced a stranger finale, with Rose ending his exile to not only reunite with Slash and Duff, but to front AC/DC, positioning himself as a cuddly slice of nostalgia and not half the monster he once was.

Mick Wall has, in my opinion, written the definitive biography of Led Zeppelin, giants of the 1970s. Last Of the Giants is another; the mad, funny, dark and often painful story of a lost band from a now-distant time.

Last of the Giants: The True Story of Guns N’ Roses by Mick Wall is published today.

The Guns N' Roses 'True Or False' Quiz: can you separate fact from fiction?