The greatest sports stars characterise their times.
They also help to tell us who we are. John McEnroe, at his best and worst, told us the story of the eighties.
His improvised quest for tennis perfection, and his inability to find a way to grow up, dramatised the volatile self-absorption of a generation.
His matches were open therapy sessions, and they allowed us all to be armchair shrinks.
Tim Adams sets out to explore what it might have meant to be John McEnroe during those times, and in his subsequent lives, and to define exactly what it is we want from our sporting heroes: how we require them to play out our own dramas; how the best of them provide an intensity by which we can measure our own lives.