The problem with books about the Beatles is that when so many writers have gone before you, it’s hard to bring something new to the story. Ian Leslie has managed to do just that. John and Paul: A love story in songs focuses in on the relationship at the heart of the band, carefully picking it apart with reference to the usual array of interviews and public statements from the principals, but also – most importantly in this case – the evidence of the songs themselves.

Depictions of Lennon and McCartney can easily slide into caricature. Depending on which camp you reside in, it’s either the idealist, revolutionary genius and the soulless, shallow, commercial sell-out, or the spiteful, troubled bully and the compositional genius who kept the Beatles going for their final glorious years. Both of those versions are too simplistic and neither of them really gets to the truth. Leslie, I think, goes a lot further than most in fleshing out the dynamic that changed the world of music and more in the 1960s.

The book’s prologue starts at the end, with Paul’s infamous ‘it’s a drag’ reaction when asked by reporters to comment on the breaking news of John’s murder. By the end of the book Leslie returns to that moment and allows the reader to understand the grief and shock behind that seemingly callous comment. He shows how John and Paul found each other as teenagers, how writing songs together resulted in an intimacy and vulnerability that secured each of them a place in one another’s lives that no one else – not Yoko, not Linda – could ever completely replace. Leslie, the author of several books on human psychology, has an eye for detail that is both forensic and at the same time emotionally sensitive. He draws back the curtain on the band’s creative hub and highlights the way that ‘their collaboration, even at its most competitive, was a duet, not a duel’.

For me, one of the delights of the book is the way that individual songs are used to demonstrate Leslie’s insights, and to support his premise that far more of them have a subtext about John and Paul then might be commonly assumed. For example, the prevalence of the phrase ‘my friend’ or ‘friend’ – in Money Can’t Buy Me Love, in We Can Work It Out, in I’ll Get You and in I’ll Follow the Sun, for example – gives an indication that the songs are more than the standard boy-meets-girl pop fare.  His analysis of She Loves You is a fine example. Leslie draws on chord structure and the song’s roots in the culture of American girl groups, finally concluding that She Loves You is at the same time a song about a boy-girl relationship and also a song about friendship between boys. Leslie also points out that the imagined scenario in the song was played out in real life eleven years later, when Paul acted as a go-between to reunite John and Yoko towards the end of Lennon’s so-called ‘lost weekend’ period.

The relationship between the two men, even when it seemed most hostile and fractured from an outsider’s perspective, is deeply interwoven into their individual identities. Leslie observes that one consistent feature of the relationship was Paul’s ‘desire, verging on a need, to steer his friend towards safe harbour.’ That sense of being bound together went both ways, and the intensity of that relationship wasn’t only forged in the crazy Beatlemania days, or their heady coming of age experiences of Hamburg; it was rooted in the hours spent eye-to-eye and soul-to-soul playing guitar in one another’s homes as teenagers, the mirror image effect of Paul’s left-handed playing only adding to the sense that each saw themselves reflected in the other.

Have I read a lot of Beatles material in the past? Did I think I knew the John and Paul story already? Yes on both counts. Did this book deepen my appreciation of that relationship? Absolutely. Will it change the way I listen to some Beatles songs? Very possibly. This is a fascinating account of intimacy and hurt, of vulnerability and self-protection, and in the end, the healing power of music and friendship.