The title of the new book The Beatles: The True Beginnings is as misleading as it is enticing. And in any event, the key to the book’s appeal lies mainly in the authors’ names.

Three brothers from the Best family put this volume together. One of them, Pete, has for 40 years been the most enigmatic of all who have been touched by the aura of the Fab Four. He was, in fact, Fab himself at one time. As the Beatles’ original drummer, he shared every step with John, Paul and George, from the band’s first gigs up to the dawn of Beatlemania. For literally just a few days he felt the hysteria and adulation that would soon change his friends’ lives, the lives of millions of kids and pop culture itself.

And then, suddenly, mysteriously, he was gone. For reasons that have never been fully explained, his colleagues kicked him out, hauled in a big-nosed guy named Ringo to take his place and roared off into history, leaving Best in the dust to deal with overnight obscurity.

Now, put yourself in his shoes. While your old pals are gallivanting around the world, becoming zillionaires, hanging out with hokey holy men or French screen sirens, you’ve got to keep paying the rent on that flat in Liverpool. Lesser men might have become pathologically bitter. Indeed, Best does admit to being annoyed, but he kept his cool and now, in the most genteel fashion, he gets his revenge.

Revenge, because The True Beginnings isn’t really about the Beatles. Rather, it’s about a cramped little nightclub and the woman who ran it Best’s mother, without whom, her sons argue, the band never would have gotten off the ground.

It was Mona Best who turned her basement into a coffee bar, named it the Casbah and installed the prototype Beatles as its resident act. “She had a lot of charisma, a lot of foresight, determination and courage,” Pete Best explains by phone from the historic cellar itself. “Consequently, she turned her humble conception into the first rock ∧ roll haven in Liverpool. The Cavern was a jazz room at the time, so all the major bands in Liverpool clamored to play at the Casbah, because they loved the club and they loved my mother. She helped the Beatles when I was with them and even after I had gone. She never got the recognition she deserved, so my brothers and I had to put that story straight.” Fortunately, Pete’s youngest brother Roag had squirreled away newspaper clips, photos and boxes of junk that would turn out to be not only valuable but, improbably, beautifully photogenic a ratty pink hat from the band’s run at Hamburg’s Kaiserkeller, owlish round glasses that John wore while helping to paint the Casbah ceiling.

Then there’s the Casbah itself, a reliquary of wall scrawlings and crumbled furniture. Photographed by Sandro Sodano, the space has a kind of shabby majesty. “We wanted to show off the beauty as well as the character of the Casbah,” Pete Best explains. “I suppose that seems like a funny way to describe it, but rock ∧ roll clubs today are like plastic palaces by comparison. The Casbah was totally different in the late ’50s in its layout and in the artistic work that went into it, so yes, we do call it a thing of beauty.” The text plays almost a subsidiary role to these images, though there is plenty to enlighten even trivia experts. (Try this: What object on the cover of Sgt. Pepper’s Lonely Hearts Club Band was lent to the band by an apparently forgiving Mona Best for the photo shoot?) And there are recollections from many who were there customers at the Casbah and in the German strip clubs where the band had its coming of age, musicians and, surprisingly, even from George Harrison and Paul McCartney.

“I didn’t actually do the interview with them,” Pete says. “Roag assumed that role because I was involved in other projects. But it was a magnanimous gesture. Like everyone else who spoke to us, they knew there was a wonderful story to be told. And just like everyone else who knew my mother, they loved her too.” Robert L. Doerschuk is the author of 88: The Giants of Jazz Piano and the former editor of Musician magazine.